By Peter Griffiths
LONDON (Reuters) - Prime Minister David Cameron has little hope of persuading other European Union states to return significant powers to Britain before a promised referendum on whether to stay in the bloc, a senior member of his pro-EU coalition partners said on Monday.
Business Secretary Vince Cable, one of the leading figures in the Europhile Liberal Democrats, said Cameron's attempts to negotiate a new role for Britain would probably be blocked by other members of the 28-nation alliance.
Speaking at a debate on Britain's future in Europe, Cable said Cameron would be better off working with other EU states to reform the bloc as a whole rather than seeking special treatment for London.
Cameron said in January he would agree a "new settlement" with the EU and hold an in/out referendum before the end of 2017, providing he wins the 2015 election.
That pledge helped appease anti-EU rebels in his Conservative Party who were challenging his authority and delivered a shot across the bows of the rising UK Independence Party, which wants to leave the bloc after 40 years.
But it upset some European partners, who warned Britain against "cherry picking" from EU rules, and prompted the United States, Japan and Australia to caution Britain about leaving.
"Fundamental renegotiation is very, very unlikely to produce any significant change," Cable told an audience in the City of London's Guildhall, an imposing medieval hall, surrounded by statues of British war heroes, including Winston Churchill and Admiral Nelson. "We should stay in and improve the system."
Pressed if Germany, France and others would end up offering some concessions to Britain to hold on to one of its biggest members, Cable said: "I'm not certain they would."
Pulling out of Europe would damage the economy, deter investors and undermine Britain's standing, he added. It is the world's sixth largest economy and has Europe's biggest financial center.
Eurosceptics think Britain will cope outside the EU, a body they see as a wasteful and meddling threat to Britain's sovereignty. They want to create a looser relationship based on trade or leave the bloc altogether.
Conservative lawmaker Jesse Norman said London's finance industry could still prosper outside the EU due to its size, time zone and use of the English language. Britain could also improve trade with emerging markets, he added.
A poll suggested the "out" campaign has a narrow lead. Asked how they would vote in a referendum by researchers TNS BMRB, 43 percent said they would opt to leave and 39 percent wanted to stay.
(Editing by Phil Berlowitz)