David Cameron: UK's EU reforms deal can be finalised by February

He denied that his demand for a four-year ban on migrants claiming in-work benefits had been swept off the table by counterparts worried about undermining the EU principle of free movement.

But European Council president Donald Tusk said there could be no "discrimination" on the basis of nationality, while German chancellor Angela Merkel promised to protect the "pillars" of the union.

Speaking at a hastily-arranged press conference after the talks - during which he had to replace a wonky British crest drooping off the podium - Mr Cameron said: "I would say today what has happened is we have taken a big step to a better deal for Britain but there is still a lot of hard work to be done, and it is going to need to be done between now and February 18.

"But there is a path through this to a better deal for Britain."

Mr Cameron said he believed questions about how to make the reforms legally enforceable could also be overcome.

"If treaty change is necessary and I believe it is there should be a way to deliver that treaty change ... I believe there is a good way through that," he said.

The premier denied that he had been forced to back down on his plan for restricting in-work benefits. "In terms of welfare, no I haven't put any other proposals on the table - I have put my four year proposal on the table and it remains on the table," he said.

"The commission said that they believed there were solutions - not compromises, solutions. I am confident after tonight that we can find solutions."

Mr Cameron said nothing was "certain" but there was clear "momentum" towards a deal, expressing confidence that it could be done by the next European Council summit in February.

"Nothing is certain in life, nor in Brussels, but what I would say is there is a pathway through this to a deal in February," he added.

At a separate press conference, Mr Tusk said he would aim to table a text on proposed reforms at the February gathering.

Mr Tusk characterised the discussions over dinner as "substantive and constructive", while again dismissing the idea that any proposals could be discriminatory.

"Prime Minister Cameron set out in detail his position, in particular regarding benefits and free movement," said the council president.

"He explained his request for a model based on four years and reiterated his openness to alternative solutions only if they could achieve the same objective.

"Leaders voiced their concerns but also demonstrated willingness to look for compromises."

Mrs Merkel suggested treaty change could achieved if needed. "It is not something that can happen now but it can later," she said.

Mr Cameron has already made clear he is willing to consider alternatives that would reduce migration "pull factors". But although officials are thought to be working on options - such as an "emergency brake" on excessive inflows or a residency test - no other plans have been formally put on the table.

In a 40-minute presentation - described by UK sources as his longest ever speech to leaders at an EU summit - Mr Cameron sought to persuade them that British worries must be accommodated ahead of the looming in-out referendum.

"The levels of migration we have seen in a relatively short period of time are unprecedented, including the pressures this places on communities and public services," he said.

"This is a major concern of the British people that is undermining support for the European Union."

The Prime Minister is under intense domestic pressure to secure substantial concessions ahead of the referendum on EU membership promised by the end of 2017. Downing Street has said his presentation to leaders - over a dinner without any of their diplomatic entourage - was designed to put some political momentum into the renegotiation process.

Mr Cameron has already been forced to abandon his initial hope that a deal could be finalised before Christmas, and now hopes it will be possible by the next summit in February. June is widely mooted as his favoured schedule for holding the referendum, before a summer in which Europe's migrant crisis could reach new heights.

French president Francois Hollande appeared to suggest at his press conference that the poll would take place in the middle of next year - but Mr Cameron denied discussing the timing over dinner.

Mr Tusk described Mr Cameron's presentation as a "make or break moment".

Mr Hollande said the tone of the meeting had been "frank and open", and had made clear "what can be accepted and what is not admissible in regard to the European rules".

The French president said: "There could be adaptations, there could be alterations, but there must be respect for the European principles, the European rules, the European assets. It is on that basis that we can pursue the discussions."

While the issues of sovereignty and competitiveness raised by Mr Cameron did not raise significant problems, his positions on a delay in welfare payments for migrants and protections for non-eurozone states were "delicate", said Mr Hollande.

Mrs Merkel said all the EU leaders had made clear that they wanted the UK to remain in the EU.

She said leaders had "made clear our readiness to compromise", but added that this was "always with a regard to the protection of the fundamental principles of the EU" such as non-discrimination and freedom of movement.

Mrs Merkel said "intensive discussions" would be required to resolve the issues by February and said it would not be simple. But she added: "I think with a good will, we can find a good way."

Vote Leave chief executive Matthew Elliott said: "David Cameron's EU renegotiation is trivial and that's why the European Council managed to sum it up in just two sentences.

"He claimed he put in 'hard work' for Britain but people will look at this and not believe his spin.

"We should take back control and spend our money on our priorities like the NHS - that's the safer option."

Ukip leader Nigel Farage said: "David Cameron came, saw, and got hammered. How many times can his little plans be rejected?

"All he got as a result was a meaningless two sentences in a communique. He was told to come back in February when I suspect he will probably get a few minor concessions."

Defence Secretary Michael Fallon insisted the UK was "deadly serious" about measures to prevent the country's benefit system being a "magnet for migration".

He played down the prospect of an "emergency brake" on migration being a suitable alternative to the welfare curbs proposed by Mr Cameron, insisting that a "short-term solution" would not be enough.

"There are problems with some of the solutions that have been canvassed to this," he told BBC Radio 4's Today programme.

"We need to stop the pull of the migration system so that you don't come here simply to get in-work benefits or have an automatic right to social housing ahead of people who are already living and working here."

He added: "We have got to find a way through this.

"It has not got to be a short-term solution ... it can't be something that is simply cobbled together for a few months or a year or two."

Achieving the "binding" and "irreversible" changes would not be "easy for our partners", Mr Fallon acknowledged.

"But Britain is deadly serious about reducing the pull, the attractiveness of our benefits system, so that we can start to reduce, rather than see migration increase."