“While we see good prospects for agreeing on ways to fight abuses and possibly on some reforms related to the export of child benefits, there is presently no consensus on the request that people coming to Britain from the EU must live there and contribute for four years before they qualify for in-work benefits or social housing.
“This is certainly an issue where we need to hear more from the British Prime Minister and an open debate among ourselves before proceeding further.”
Critics have also warned any deal Mr Cameron could get is still likely to be struck down by the European Court of Justice as it runs against rules that mean no EU citizen can be discriminated against due to their nationality in any other EU country.
The Prime Minister’s demands will be debated at an EU summit this month
There is presently no consensus on the request that people coming to Britain from the EU must live there and contribute for four years before they qualify for in-work benefits or social housing
Instead, the earliest the European Council will form a blueprint for EU reform will be in February, when Mr Tusk said he hoped for a “concrete proposal” to be adopted.
This will push back the likely date of the in/out vote until next Autumn.
Eurosceptics pointed to yesterday’s opposition to the Prime Minister’s demands by Mr Tusk as a further sign a ‘sham’ renegotiation exercise was being played out in front of the British public.
Mr Tusk described Britain’s possible exit from the EU – known as Brexit – as a “destabilising factor” for the 28-member-bloc as it faces a number of other crises, such as the Greek debt crisis, migrant crisis and souring relations with Russia.
He added: “That is why we must find a way to answer the British concerns as quickly as possible.
“In times when geopolitics is back in Europe, we need to be united and strong. This is in our common interest and in the interest of each and every EU Member State.
“The UK has played a constructive and important role in the development of the European Union and I am sure that it will continue to do so in the future.”