London also said it was firmly behind a bid by Turkey to join the 25-member club, once accession talks that begin 3 October are completed.
Prime Minister Tony Blair is to mark the start of his six months at the helm of the European Union by holding talks with European Commission President Jose Manuel Barroso and the other commissioners in the British capital.
They are to give a news conference at about 3pm (1400 GMT) on Friday.
The next six months are expected to be stormy, as EU members struggle to agree on a budget for 2007-2013, while reflecting on the failure of a draft constitution that was recently rejected by French and Dutch voters.
"It's an uncomfortable situation that all of us are in in Europe at the moment," said Britain's Foreign Secretary Jack Straw.
"But, as the prime minister said in the speech he made last week, out of a crisis can come an opportunity," he told BBC radio, referring to an address made by Blair at the European parliament in Brussels.
Crisis in Europe
"In many ways I think this was a crisis, a problem, waiting to happen in Europe," Straw said.
"What we now have to do is use the position we have as president of the EU to provide leadership and to provide leadership, however, in a conciliatory way."
Blair has stated his desire to reform Europe's generous system of farm subsidies under the Common Agricultural Policy (CAP), while at the same time reviewing a controversial budget rebate granted to Britain in a sweeping shake-up of the bloc's long-term financing.
"What we now have to do is use the position we have as president of the EU to provide leadership and to provide leadership, however, in a conciliatory way"
British foreign secretary
He contends that it is wrong for the EU to spend 40% of its budget on farming when it should put more into research and development to deal with the challenge of globalisation.
British, French clashes
Such reform will likely trigger a new clash between Blair and French President Jacques Chirac, who is determined to protect the generous CAP payouts to farmers, which heavily favour the French.
"What we wanted to achieve was a presidency which was workmanlike, which was efficient, which got through the business in the interests of the European Union as a whole," a senior British official said.
The official admitted that negotiating among the member states would be a "delicate task".
"Let's focus on the debates rather than the fireworks," the official said.
Collapsed spending plans
Prospects of agreeing to future EU spending plans an EU summit in Brussels collapsed two weeks ago when Britain refused to give up its budget rebate without a guarantee of changes to the bloc's farm subsidy scheme.
The setback added to the mood of crisis in the European Union after voters in France and the Netherlands rejected the EU constitution in referendums last month.
Jack Straw reiterated Britain's
backing for Turkey to join the EU
Setting out Britain's plans for its presidency, Straw on Thursday reiterated Britain's firm backing to Turkey joining the bloc, once accession talks that begin 3 October are completed.
Straw said the EU stood ready to open membership talks with Croatia, so long as Zagreb cooperates with the UN war crimes tribunal, and that it looks forward to admitting candidate states Bulgaria and Romania from 2007.
In addition, the British EU presidency will see a number of bilateral summits, notably with China, India, Russia and Ukraine.
Britain will also represent the EU at the UN Millennium Summit in New York in September.