Prime Minister David Cameron has suggested motorists take the “sensible precaution” of topping up on petrol ahead of a potential strike by fuel tanker drivers.
Cameron’s comments come just hours after Francis Maude, the Cabinet Office Minister, said any potential strike would put lives at risk.
Maude advised drivers to fill up any spare jerry cans with petrol, even though motoring organisations and energy firms have urged people not to panic buy.
He accused the Unite union of behaving irresponsibly, adding that a "couple of hundred" military crews would be trained to cover for striking tanker drivers in a bid to maintain supplies to hospitals and schools, as well as garages.
However, the Fire Brigades Union urged Maude to withdraw his advice to stockpile fuel, warning it would "massively increase" the risk of fire and explosions.
Matt Wrack, FBU general secretary, said: "This is not sensible advice…Those without garages may be tempted to store fuel in the home. In the event of a fire in the house or a neighbouring property, it would be disastrous.
"It is already against the law to store more than 10 litres of petrol in two five-litre plastic containers in the home. As that amounts to little more than a third of a tank in most cars, the advice is of little practical help.
"There is a real danger the public will start storing fuel in inappropriate ways if the Government is encouraging panic-buying and storage. This advice is wrong and must be withdrawn."
Responding to the FBU's warning about the dangers of stockpiling fuel, Mr Maude told BBC Radio 4's World at One: "There are legal limits on what you can store, very sensibly, and they have been in existence for some time and I am sure the fire service will communicate this.
"There are perfectly sensible regulations surrounding this, which people will no doubt obey.
"It sounds like people are behaving in an extremely sensible way. There is no kind of dramatic action. Where there is an opportunity sensibly, calmly, to get a bit more fuel they are doing that without any drama.
"There are sensible low-key things that can be done and if they choose to do it, that's one of them, obviously within sensible constraints." The civil contingencies committee Cobra will meet later to discuss measures they will put in place in the event of fuel tanker drivers with the Unite union going on strike.
Unite drivers, who have already voted to go on strike over health and safety standards and terms and conditions, supply 90 per cent of petrol stations in the UK.
Responding to accusations by Labour that the Government had caused alarm by giving people the impression they should panic buy, David Cameron said: "There is no imminent strike. The unions would have to give seven days' notice of any strike so there is no need to queue to buy petrol.
"If there is an opportunity to top up your tank if a strike is potentially on the way, then it is a sensible thing if you are able to do that."
He added: "I absolutely do not want to raise the temperature on this any more than is necessary."