Conservative MPs have branded a draft proposal to renegotiate the terms of European Union membership for Britain "thin gruel" as David Cameron took questions on the package in Parliament.
The Prime Minister said the raft of measures was the “strongest package ever” to deal with immigration issues caused by the bloc.
Jacob Rees-Mogg, a leading eurosceptic backbencher told the PM that "the thin gruel has been further watered down". He declared that the Prime Minister had a fortnight to "salvage his reputation as a negotiator".
The Prime Minister mounted his defence in a statement to MPs on Wednesday afternoon – about 24 hours after the proposed deal was released by the European Council president Donald Tusk.
Mr Cameron’s deal has however has been criticised by many eurosceptics, including those within his own party.
Former defence secretary Liam Fox branded the document “watered down in every area” while Sir Bill Cash said Mr Cameron had “bypassed so many promises and principles”.
The response from eurosceptic newspapers to the deal has also been negative, with The Sun saying it “stinks” and the Daily Express branding it “a joke”.
The interventions come amid speculation about which of Mr Cameron's own Cabinet ministers could campaign on the opposite side of the referendum from him - in favour of exit.
Mr Cameron however said the “legally binding” agreement represented “real progress” but that the process was “far from over”.
“We want to deal with the pressures of immigration, which have become too great,” he told the House of Commons.
“The draft text represents the strongest package we’ve ever had in tackling the abuse of free movement and closing down the backdoor routes the Britain. There are new proposals to reduce the pull factor that our benefit system exerts across Europe by allowing instant access to welfare from the day someone arrives.
“People said that Europe wouldn’t even recognise that we had this problem, but the text explicitly recognises that welfare system can act as an unnatural draw to come to this country.
“[We’ve secured proposals for] an emergency brake that will mean people coming to Britain from within the EU will have to wait four years until they have full access to our benefits. The European Commission has said Britain qualifies already to use this mechanism so with the necessary legislation we’ll be able to implement it shortly after the referendum.”
“People said we would never get something that was legally binding but this plan, if agreed, with mean exactly that.”
Labour’s leader Jeremy Corbyn said the reform package lacked serious measures to deal with the supposed impact of migration from the EU and laid out Labour’s approach.
“What the Prime Minister described as the ‘strongest package ever’ to tackle the abuse of free movement doesn’t actually begin to tackle the real problems on the impact on migration of jobs, wages and communities,” Mr Corbyn said.
“Those demand action in areas of high population growth to support public services and regulation to prevent the subsiding of low pay and the grotesque exploitation of migrant workers by some very unscrupulous employers.”
Mr Corbyn said Labour welcomed another aspect of the package, a power for national parlaiments to block new EU legislation.
The Prime Minister had previously said he would negotiate new rules so that EU migrants “must live her e and contribute for four years before they qualify for in-work benefits or social housing”.
However, Mr Cameron has only been offered powers to limit in-work benefits partially, with the amount of social security paid to migrants gradually increasing over the four year period.
Mr Cameron will have to convince other EU nations at a summit later this month as well as his own MPs and the British people of the deal’s effectiveness.
After the deal is taken forward Mr Cameron will hold a referendum on European Union membership – expected before the end of 2017 but possibly as early as this summer.
After pressure from the Scottish Welsh, and Northern Ireland governments Mr Cameron said the referendum would not be held closer than six weeks after the local and regional elections this May.
Those devolved administrations are seeking further assurances on the matter of timing, however.
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