Cheering from the sidelines: Cameron calls for a “strong and successful” eurozone Photograph: Reuters

Before Britain’s general election, Brussels feared the advent of the most Eurosceptic UK government since Margaret Thatcher wielded her handbag at her EU “partners”.

David Cameron, the Conservative Party leader, duly became prime minister. But a very different landscape for Britain’s relationship with the EU has suddenly loomed into view. The Tories’ partnership with the Liberal Democrats, the most pro-European of Britain’s three main parties, in the country’s first coalition government since the Second World War could have a dramatic impact on UK-EU relations.

In Britain, it is the small band of Europhiles in Cameron’s party, rather than the dominant group of sceptics, who have a spring in their step. They hope their Lib Dem partners will provide cover for Cameron to marginalise the sceptics and adopt a much more positive approach to Europe than he could have if the Tories had won an overall majority in May.

Denis MacShane, Labour’s former minister for Europe, gives the Liberal-Conservative coalition “seven out of ten” on Europe. “I would like to beat them up for being manic Eurosceptics but the plain fact is that, so far, they are not,” he says. “As he pushes through his Blairisation of his Conservative Party, David Cameron is also making his peace with the EU.”

European diplomats, mystified by what a Cameron-led government would bring, are pleasantly surprised by the positive noises about EU engagement from the new coalition as it tried to avoid rows over hedge funds, a levy on banks and the euro crisis. At his first EU summit in June, the prime minister went out of his way to avoid a row and promised a “pragmatic and sensible” approach as he pressed the flesh with his new colleagues. The inevitable caveat, largely for domestic consumption, was that he would defend the national interest where necessary.

Some Tory Europhiles dare to talk of Cameron taking on a pivotal role in Europe, exploiting its leadership vacuum and the poor relationship between Nicolas Sarkozy and Angela Merkel, the French and German leaders and, against the odds, making Britain a big player at the EU’s top table. Some even predict that Tory MEPs will rejoin the European People’s Party (EPP), the main centre-right grouping in the European Parliament, which Cameron pulled his party out of last year on the grounds that it was too federalist.

S......