How would you make London greener?
In every way, of course, but greener homes and greener travel are the most urgent as the majority of London's emissions come from those two sources. My plans all aim to make London more affordable as well as greener, so I'd reduce people's bills at home by making free insulation available to everyone, not just pensioners and people on benefits. On transport, I'd invest much more in helping Londoners walk and cycle around the city, and reduce the cost of public transport with a 20p fare cut as well. I have lots of other ideas, but I think these will make the biggest difference.
How do you propose to match Ken Livingstone's £500m scheme to turn London into a true cycling city?
£500m sounds like a lot, but that's spread out over 10 years so it's only £50m each year. The Greens on the London Assembly have a casting vote over the Mayor's budget at the moment, so the fact cycling funding is up from less than £20m in 2004 is a great achievement for us. But as Green Mayor I'd triple this again. Our current targets for cycling are still low compared with other European cities. If we can't get more people cycling than using the Tube and bus by 2025, that will be a real waste of our city's potential.
You campaign against 4x4s. Do you have any friends who drive them? Would you refuse to go in one?
Friends of my friends have them, and I know they get a lot of stick at dinner parties. It's not so much the type of car you have as where you use it that matters, so if someone is a farmer that's fine, but 4x4s have no place in the city. I hardly ever need to get a lift, but I did spend a day driving round Gloucestershire in Dom Joly's 4x4 for a TV programme recently. Needless to say, he didn't convince me it was strictly necessary.
How do you travel around London?
By bus, Tube, bike and – very occasionally – a taxi. I like to walk as well, and will cover two or three miles happily on foot, as long as I'm in my comfortable boots. London needs better signs for pedestrians to make walking more of an option for people – especially the tourists who take the Tube for a couple of stops when they don't need to. That's another thing the Greens have got past the Mayor. Bond Street now has some excellent signs for people who want to walk, and I'd expand this to the whole city if I was Mayor.
Do you think Lee Jasper is the victim of racism?
The campaign against him has certainly been interpreted by some people as racially motivated. I don't think that was the intention of those involved but I read Andrew Gilligan's interview in The Independent recently, and I didn't like the way he described setting out to trap Ken Livingstone and Lee Jasper, rather than reveal his information to the public all at once.
How would you sum up Ken Livingstone's contribution to London in his time as Mayor?
He has done quite a good job of representing Londoners, but recently he has become too close to big businesses and people wanting to build towers and office developments and hasn't focused enough on what people need, which is more affordable housing. In contrast, he has done much more on climate change in his second term, which I put down to the influence of Darren Johnson and Jenny Jones, the Greens on the Assembly. He does respect us now, and is willing to work with us on making London greener, which in his first term was a bit of a forgotten issue.
What are your five favourite London landmarks?
Towers and edifices don't impress me much, so I'll have to say Parliament Hill, the Natural History Museum, Kew Gardens, the Round Pond in Kensington Gardens (complete with mad, swooping swifts) and the river Thames.
What are the best things about living in London? And the worst?
The best thing is that people from everywhere in the world live here and are willing to cook for me. We have the best range of food anywhere. The worst thing is the dirty, polluted air we have to breathe, which kills more than a thousand of us every year and needs urgent action to clean it up.
How do you propose to tackle the problem of teenage gun and knife crime in London?
With real community policing, not macho, high-tech gimmicks. I'd give Safer Neighbourhood Teams more officers and shifts rather than spend money on metal detectors and ultrasonic "youth deterrents". The main factor making these problems worse is the chronic lack of things for young people to do, so I'd increase funding for youth services to make up for some of the cuts local councils have put in. I'd also fund projects with more long-term grants so staff can get on with their work, rather than spending half their time applying for the next round of funding.
Ken Livingstone has been notably supportive of Met police chief Sir Iain Blair. Do you feel equally supportive?
I believe that the tragic shooting of Jean Charles de Menezes showed catastrophic failures in the way armed police in London were organised and deployed, for which Sir Ian Blair, as the commissioner, was responsible. So, although he has done many good things too, I called for his resignation and don't think he should have stayed on.
Should we have airport-style security checks at London Underground and overground stations?
No. Not only would that be completely impractical, but it would also mean that London, as a city, had completely lost all faith and trust in its citizens.
Aren't the Olympics a disaster for London and the environment?
We do need investment and regeneration in the areas where the Olympics will be held, but I do sometimes wish we could just take the "legacy' part of the 2012 Games for London and not all the rest. Recent developments, such as the forced adoption of Coke and McDonald's as food sponsors and the request for IOC officials to have a fleet of chauffeur-driven limousines, are worrying. As Mayor, I'd work hard to make sure environmental promises and commitments to bring benefits to the local area are kept, and I'd put the bigwigs on the bus as well.
The congestion charge has reduced traffic, but not congestion. Will you scrap it?
The congestion charge has worked. We're the only major city which is increasing the share of people using public transport, and we've seen a huge increase in cycling too. And motor traffic, while the gains are small, isn't getting worse in contrast to every other region of the UK.
I'd also keep the policy of having a higher charge for gas-guzzlers, which will have a huge effect on the motor industry's priorities, especially as other cities are now adopting the same kinds of schemes. This is something I've campaigned for since 2003, so I am really pleased it's coming in at last, and would plan to strengthen the emissions requirements over time.
Why has the UK never developed a strong Green Party?
We're getting stronger all the time – especially in London, where we had more than 13 per cent of the vote at the local council elections two years ago. We do suffer under first past the post. Even though we have about the same support as in Germany, the German Greens have had MPs and even cabinet ministers because they have a proper proportional voting system. Similarly, in the Scottish Parliament and the Northern Ireland Assembly, people have elected Greens through PR.
In May, the London-wide Assembly election is also done under PR, so we have a real chance there to increase our representation and achieve even more than we have done with two AMs.
If you had to vote for one of your opponents, who would it be?
You'll have to wait for an answer to that one. People have two votes in the mayoral election and the London Green Party is currently in the process of deciding whether or not to make a recommendation for where our second votes should go, which we didn't do at the last election in 2004. We'll be having a democratic vote to decide at a meeting on 17 March, so watch this space.
I find using public transport inconvenient and sometimes threatening. Why shouldn't I use my car?
My transport plans are all about demolishing the idea that you have to choose one "transport tribe" for all your journeys. I want to make it easier for people to use a free street bike for some journeys, and make it more convenient and cheaper to get on the train or the bus for others, so people will only want to use their cars when they are really needed. Hopefully, in the future, you'll find you feel more confident to try different ways of getting about.
What's the proof for climate change?
It's already happening. My mum and dad back in Cheltenham spent several weeks with floods, no running water and almost lost their electricity supply completely this summer, which has never happened before. The fact that higher levels of carbon dioxide will trap more heat in the atmosphere is indisputable, and humans have created the high levels we have today.
The effects in other countries will be much worse. However, in London, we are still vulnerable to rising sea levels, heatwaves and many other effects of rising temperatures, so we absolutely have to do our bit to reduce the problem.
You'll never get people out of their cars. Why don't you concentrate on helping make cars greener using better technologies?
I do that all the time. The new congestion charge has discounts for cleaner cars and, with the Alliance Against Urban 4x4s, I've spent a lot of time talking to manufacturers and working on new EU rules so they can reduce their emissions steadily over the next few years. We don't just have a go at big urban 4x4s, we also praise people who choose smaller, cleaner cars, and even leave valentine cards under their windscreen wipers every year.
Do you like Boris Johnson, and are you alarmed that he might actually win?
I've only met him a couple of times because he's been quite poor at turning up to hustings so far, but he does come across as quite amiable. I'm very worried about what would happen to London if he became Mayor. The Conservatives – unlike Labour – wouldn't need anyone else's Assembly votes to pass the London budget. So we'd have a Tory monopoly, led by Boris Johnson, running London for the next four years, which is a very alarming prospect.
Are you a vegetarian and if so why?
I'm not completely vegetarian, but I eat very little meat and have a lot of veggie meals. Meat and dairy production create many more greenhouse gas emissions and uses much more water than growing vegetables and cereals.