By Stephen Brown and Mark John
BERLIN/PARIS, Jan 23 (Reuters) - Britain's European partners heaped scorn on Prime Minister David Cameron's demand for radical reform of the EU and promise of an "in-out" referendum on UK membership, calling it reckless and ignorant of EU decision making.
"If Britain wants to leave Europe we will roll out the red carpet for you," quipped French Foreign Minister Laurent Fabius, a barbed riposte to Cameron who last year used the same phrase to invite wealthy French tax exiles to Britain.
Demanding changes in the rules was as if Britain had joined a football club and then suddenly said "let's play rugby", said Fabius.
German Foreign Minister Guido Westerwelle said Britain could not treat Europe like an "a la carte" menu from which it could pick and choose policies it liked.
"Cherry-picking is not an option," he said.
Martin Schulz, the head of the European Parliament which with the European Commission was the butt of Cameron's criticism of "sclerotic" EU decision-making, was just plain angry.
Britain was pointing the finger but was "overwhelmingly to blame for all the delays in Europe", said Schulz. "He just wants change in the single interest of Britain and that's not fair."
In Germany, where Angela Merkel's conservative sympathies for Cameron's party are overshadowed by anger at their exit from the centre-right EU bloc and his veto of her fiscal pact, the view is that the UK premier has painted himself into a corner.
German politicians face eurosceptic pressures of their own but say Cameron pays too much attention to a loud minority.
"Cameron is using EU membership as a tactical tool for domestic politics," said Manuel Sarrazin of the German Greens.
The response to Cameron's long-awaited speech was not uniformly negative. Among sympathisers was Czech Prime Minister Petr Necas, whose government was the only one other than Britain's not to sign the fiscal pact. He said he shared Cameron's wish for a "more flexible, more open" EU.
Mark Verheijen, a lawmaker from Dutch Premier Mark Rutte's Liberal Party which shares Cameron's concerns but does not want an opt-out, called it a "strong speech" with good reform ideas.
But such voices were largely drowned out by those who saw danger for the European project if countries were allowed to demand opt-outs from EU policies they did not like.
Carl Bildt, the Swedish foreign minister, said the idea of flexible membership floated by Cameron "sounds fine" but would lead to there being "no Europe at all. Just a mess."
PLAYING WITH FIRE
Even if opinion to Britain were warmer, it is far from clear how it could initiate and successfully pilot a treaty negotiation, EU officials said.
Guy Verhofstadt, former Belgian prime minister and now leader of the liberals in the European Parliament, said the British premier was "playing with fire" by trying to renegotiate EU membership and put it to the vote.
"His speech was full of inconsistencies, displaying a degree of ignorance about how the EU works," said Verhofstadt.
Verhofstadt said granting Britain wholesale opt-outs from common European rules and regulations risked precipitating an unravelling of the EU and its internal market.
The alarm is not confined to Europe. Britain has also been warned by the White House and a host of business leaders that it would lose global influence if it left the EU.
Joseph Nye, a former U.S. defence department official and professor at Harvard, said "Europe with Britain in it is much more powerful and important than without it". President Barack Obama "very much wants Britain to remain in the EU", Nye told a panel at the Davos World Economic Forum.
Among those defending Cameron were Austrian Eurosceptic Hans-Christian Strache of the far-right Freedom Party, who called the criticism of the British leader "hysterical".
Finland's Europe minister, Alex Stubb, said he did not think Cameron wanted to quit the EU.
"He wants to get this discussion done and clarify Britain's position in the EU once and for all. In that sense I do respect his line," he said.
Cameron gave EU leaders advance warning of his speech and some, even if they did not like what they heard, agreed with him that it was high time for an honest debate about reform.
"It is time, as Cameron said, for a more intense debate on democracy and transparency in the EU," said Sweden's EU Affairs Minister Birgitta Ohlsson. "But we can discuss these issues within the EU."
EU diplomats said plans for a referendum in 2015-2017, based on proposals that had not yet been proposed much less negotiated, allowed for far too much uncertainty.
"Basically it boiled down to: 'Let's re-elect me, let's then change our ties with Europe, and then let's have a referendum on something that's not defined yet'," said one EU diplomat.
Peter Mandelson, a former EU trade commissioner and veteran British government minister from Cameron's Labour opposition, called it a "schizophrenic" speech and said Europe would not respond positively to being treated as a "cafeteria service where you bring your own tray and leave with what you want".
Jolyon Howorth, a British scholar of European politics, said the EU might be better off without Britain as it would then be free to work towards the vision of a federal Europe, "unhampered by the brake-man on the caboose".