Demonstrations across the globe mark Bali summit

Hundreds of thousands of people around the world are expected to take part in a global protest today to highlight the effects of climate change.

Demonstrations have been called for in 86 countries to coincide with the international UN Climate Talks in Bali. Protesters will be demanding urgent action from world leaders to do more to prevent the destabilisation of the Earth's climate.

In Britain, mass demonstrations will take place in London and Glasgow and a number of direct action environmental groups are also expected to stage their own form of protests.

Organisers in London are expecting tens of thousands of people to join the march which will converge on the US embassy in Grosvenor Square in protest at the Bush administration's reluctance to sign up to key climate treaties.

With all eyes fixed on the international climate summit in Bali, environmental activists will be hoping for a high global turnout to pile pressure on the leaders of developed nations to embrace tougher reductions of carbon emissions and to do more to alleviate those countries most vulnerable to the effects of climate change.

The mass demonstration in London will begin at 12pm on Millbank, following a route via 10 Downing Street and the Houses of Parliament before heading towards Trafalgar Square and the US embassy. A separate "cycle protest" will assemble at Lincoln's Inn Fields at 10am.

Speakers at the protest will include the Liberal Democrat leadership contender Chris Huhne, Caroline Lucas from the Green Party and the environmental campaigner George Monbiot.

The march in Glasgow will begin at 12.30pm at West Street Subway. There will also be workshops and debates designed to empower people into undertaking positive programmes for change and sustainable living solutions.

The protest organisers said they hoped "ten of thousands" of demonstrators would turn out for the march in London although there were concerns poor weather may stop people from coming on to the streets. Last year 20,000 protesters turned up to a similar march, but many campaigners have since expressed disappointment that attendance still remains in the low tens of thousands for a global issue while the anti-war marches in 2003 led to the largest protests Britain has seen.

Phil Thornhill from the Campaign against Climate Change said: "As the Arctic shrinks before our eyes and warnings from the scientists reach a deafening crescendo, still world leaders fail to take any effective action to head off looming catastrophe. As Greece and California burn, as Bangladeshis drown and Britain floods, alarm and anger around the world are beginning to mount, above all against the Bush administration ... and its calculating obstructionism at the international climate talks."

Yesterday, a group of female environmental activists demonstrated outside the Department of Transport, by attaching themselves to the ministry's doors using super-glue and bicycle locks.

Jane Fairbrook, a cycle store owner, who glued herself to the door, said: "We're doing this in solidarity with the women around the world who are already suffering the effects of climate chaos."

The Metropolitan Police last night said they had arrested seven women for either, or both, aggravated trespass and "staging an unauthorised demonstration in a designated SOCPA [Serious Organised Crime and Police Act] area".