Now Cameron fuels Eurosceptic anger over EU treaty vote

David Cameron has upset Eurosceptic Conservative MPs by refusing to promise a retrospective referendum on the EU Reform Treaty should his party win the next general election.

Nearly 40 Tory MPs have signed a Commons motion tabled by Bill Cash, the arch-Eurosceptic and MP for Stone, which calls for a referendum "before or after ratification" by Parliament. Signatories include the former ministers John Redwood and Michael Ancram.

Speaking at his monthly press conference yesterday, Mr Cameron said such a commitment would depend on "six ifs" – if the opponents of the treaty failed to defeat the Government in the Commons; if they failed in the Lords; if the Prime Minister did not change his mind; if there was not an early election; if every other country ratified the accord; and if no other EU state held a referendum on the issue.

"We simply don't know all of those things," he said. "I am not going to do anything that undermines the focus we have on getting that referendum now."

The Tory leadership is campaigning for a ballot now but does not want to go into an election battle promising to call a public vote on the Reform Treaty within two years. It fears this would make the party look as if it was obsessed once more with Europe.

Mr Cameron said he wanted to shift to a fresh agenda, focusing on school reforms next month, then welfare and security issues in January. Six Tory policy groups have been wound up but other working parties are to deliver proposals designed to improve the lives of children, and to give people more say in local government, he added.

He also signalled that cross-party talks about political funding were on the verge of collapse because of his demand for union donations to the Labour Party to be capped at £50,000.

Sir Hayden Phillips, who is reviewing party funding, will hold a make-or-break meeting with party leaders this month. Last week, Mr Cameron told Gordon Brown he would not agree to a shift towards state funding unless a cap on union donations to Labour was agreed. The impasse raises doubts that a deal to reform funding can be struck before an election, which would be fought on existing rules which limit campaign spending to about £20m.

The Conservatives were prepared to surrender the right of individuals such as Lord Ashcroft, the millionaire Tory donor, to bankroll campaigns in marginal target seats in return for a cap on union donations – but Labour refused.

Mr Cameron said talks about the extension of state funding could not be justified unless donor limits applied across the board. He added: "If not, I see little point in [the negotiations]."