'Brexit' negotiations still face difficulties: European Commission

(BRUSSELS) - Negotiations on Britain's demands to stay in the EU still have difficult issues to resolve before a hoped-for deal in February can be struck, a top European Commission official said Thursday.

Jonathan Faull, head of the British referendum task force at the Brussels-based Commission, said there was the "political will" to achieve an accord at a summit next month but that there was still work to do.

"We have only a few weeks left. There are still difficult issues remaining to be resolved," Faull told a European Parliament committee when asked to rate the chances of a deal.

"I'm not a betting man and I'm not going to put money on it and I wouldn't encourage you to either. But I think there will be very intensive discussions, and from what I can see the political will to resolve this issue is pretty strong."

Faull, one of the few senior British officials at the European Commission, the 28-nation EU's executive branch, admitted that the negotiations involved "fundamental issues" for the bloc.

British Prime Minister David Cameron has said he is reasonably confident of a deal in February on the changes he is seeking in four key areas, ahead of a referendum expected in mid-2016 on a possible "Brexit" from the bloc.

His most controversial proposal is a four-year ban on top-up benefits for EU migrants working in Britain, which critics say is discriminatory and threatens freedom of movement in the EU.

But there is less opposition to his other demands -- for the European Union to give Britain safeguards against more political integration, to protect countries that do not use the euro currency and to boost economic competitiveness.

Cameron has said it may be necessary to change the EU's treaties to achieve his aims, a cumbersome process, but Faull said there were various other ways of making the changes legally binding.

He added that Commission was "working to keep the UK in the EU because we believe it's in the interest of the EU, and without interfering in any way, we believe it's in the interest of the UK."

The Briton added that he himself is unable to take part in the referendum.

"I don't even have a vote myself, I've lived abroad too long," he said.