London: Prime Minister David Cameron will on Wednesday defend planned reforms to keep Britain in the EU before parliament, as European lawmakers begin negotiations in Strasbourg to avoid a so-called "Brexit" from the bloc.
EU president Donald Tusk unveiled proposals to avoid Britain leaving the 28-nation club on Tuesday, firing the starting gun on two weeks of tense negotiations to reach a deal at a summit later this February.
They include a four-year "emergency brake" on welfare payments for EU migrant workers, protection for countries that do not use the euro and a "red card" system giving national parliaments more power.
Cameron said Tusk's plans showed "real progress" and made it likely that he would campaign to stay in the European Union in a referendum expected in June.
But he will likely face tough questions from British lawmakers, including eurosceptics from his own Conservative Party, who greeted the plans with scorn — one of them even accusing the premier of "polishing poo".
They are also expected to be a hard sell for some EU states, which fear Cameron is winning too many concessions ahead of a 18-19 February summit.
Negotiations are set to begin at the European Parliament on Wednesday, before Cameron begins a charm offensive that will take him to Poland and Denmark on Friday then Germany next week.
"To be, or not to be together, that is the question which must be answered not only by the British people in a referendum, but also by the other 27 members of the EU in the next two weeks," Tusk said in a letter to EU leaders.
London's bid to transform its EU membership has added to turmoil in the bloc as it struggles with its worst migration crisis since World War II and the fallout from the eurozone debt saga.
The British premier said Tusk's proposal showed he had "secured some very important changes".
"If I could get these terms for British membership I sure would opt in for being a member of the EU," Cameron said in a speech in southwest England.
But British eurosceptics were unconvinced, with London Mayor Boris Johnson, from Cameron's party, saying he had "doubts" about their effectiveness.
UK Independence Party head Nigel Farage dismissed Tusk's proposals as "pathetic," while conservative Steve Baker said the prime minister was just "polishing poo".
Opinion polls are split on whether Britons would back leaving the EU in their first vote on the subject since 1975.
Tusk's most controversial proposal is an "emergency brake" that would allow any EU state to limit the welfare payments migrants from other European countries can claim for up to four years after their arrival.