Sir Ed Davey has called on the government to immediately cut fuel duty by 10p a litre until Christmas, part of a wider package of policies aimed at cutting the cost of living. Because nothing energises a party conference quite like the prospect of marginally cheaper petrol.

The Liberal Democrat leader is also urging the government to scrap a permanent increase in fuel duty set to take effect in January. Fuel duty was frozen under the Conservatives in March 2022, and Sir Keir Starmer's government continued the freeze, deciding in May to push back a planned 3p increase in September until the end of this year. So the can has been kicked, and now the Lib Dems would like to kick it somewhat harder.

The Lib Dems claim cutting 10p from fuel duty now would mean fuel dropping by 12p per litre at the pump - a figure that presumably comes with a footnote about retailer generosity that may or may not materialise.

Sir Ed claimed drivers should be supported and that a temporary three-month fuel duty cut would pay for itself by stimulating the economy. "Petrol and diesel prices are higher than they've been for a long time because of Trump's mad war with Iran, and people need help now," he said, deploying the time-honoured political tactic of blaming someone else's war for your local petrol station's price board.

The policy would cost about £2bn, he said, adding: "It's a three-month package, a temporary package, but if you look at the extra money the government will get through the energy profits levy, from gas taxes, from VAT and fuel duty, it's self-funding." A self-funding spending pledge - a genre of political arithmetic that has never once raised eyebrows.

In a speech to his party's conference on Tuesday, Sir Ed will make further calls to cut the bus fare cap from £3 to £1, and reduce rail fares by 10%. He will also call for VAT to be dropped from public charging points for electric vehicles and a review of network costs the Lib Dems have labelled unfair. So: cheaper driving, cheaper buses, cheaper trains, cheaper EV charging. The only thing not getting cheaper, apparently, is the cost of making promises.

Chancellor John Healey is under pressure to raise taxes or cut spending at his Budget next month, amid soaring government borrowing costs - a fiscal backdrop that makes a £2bn giveaway sound like a fun idea for someone else to implement.

Asked about Sir Ed's call for a fuel duty cut, Labour Party chair Bridget Phillipson told Laura Kuenssberg: "I'm sure John Healey will be open to any and all suggestions ahead of the budget but actually this is an area where the Labour government has taken action on fuel duty already. Whilst I recognise what the Lib Dems have to say on this topic, this is the element of politics about it - they've got their conference, they're making their pitch, good luck to them." Translation: noted, filed, and gently patted on the head.

Davey says Lib Dems are 'firewall against Farage' as conference begins - because if there's one thing a party conference needs, it's a dramatic metaphor about firewalls.

Not just 'Nice Guy Eddie': Lib Dems eager for leader to show radical side at party conference. Radical, in this context, meaning a temporary fuel duty cut and a bus fare cap reduction. The revolution will be subsidised.

Join EU migration pact to tackle small boats, says Ed Davey - a reminder that the Lib Dems do have other policies, even if the conference headlines keep drifting back to petrol prices.

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