Enda Kenny and David Cameron came to one another's aid on Monday as each prepares to face a crucial test that will determine their place in history.

The imminent general election will give the Taoiseach a chance to become the first Fine Gael leader to win two successive terms in office.

After Britain's forthcoming referendum, Mr Cameron will be the prime minister who secured Britain's place in the European Union or the man who led his country out of it.

The prime minister went as far as he decently could towards endorsing the Taoiseach in the election – a little further, in fact, than most politicians might think wise in dealing with the affairs of another country.

And Mr Cameron used their joint press conference at 10 Downing Street to trumpet the Taoiseach’s prowess on the international stage.

"Enda is very respected in the European Council as someone with great experience and knowledge of how the organisation works," he said.

The British prime minister has no closer ally in Europe as he prepares for next month's summit in Brussels, which will discuss Britain's reform demands. Although he insisted again on Monday that he was in no hurry to reach a deal, there is little doubt that Cameron's preference is for an early deal and an early referendum.

Hardcore Eurosceptics

To this end, London is keen to get the message across to other European capitals that Mr Cameron sees no value in staging a phony or operatic bust-up at next month’s summit. The prime minister knows that nothing that happens at the summit could persuade hardcore British Eurosceptics that he has won a good deal, so he is happy to dispense with the histrionics.

“If there is a good deal on the table, I’ll take that deal,” he said on Monday.

Britain’s hopes for an early deal rest on European Council president Donald Tusk, who will next week present a draft text aimed at resolving Britain’s concerns. That text will form the basis for negotiations at the summit and London hopes that it will be sufficiently “realistic” in addressing Mr Cameron’s concerns to make an agreement possible.

The most difficult issue remains Britain’s proposal to make workers from other EU countries wait for four years before qualifying for welfare benefits. Mr Cameron knows this is not achievable but he needs some alternative measures that he can present as an effective disincentive to inward migration to Britain.

The Taoiseach acknowledged that some “complications” remained but expressed optimism that they would be overcome. A number of times during the press conference at Downing Street, Mr Kenny stressed the positive case for Britain remaining in the EU, arguing that Mr Cameron’s reform demands represented an opportunity for Europe. The prime minister struck a similar tone, urging voters to focus on the benefits of membership of a reformed EU.

“We should be focusing on the positive opportunity for Britain. Imagine the scale of the prize if we can remain a member of the single market – with 500 million consumers, a quarter of the global economy – with a seat at the table, a say over the rules, making sure we do right for business, jobs and investment in the UK combined with action to make sure we deal with the things that frustrate people about the EU,” he said.