By Jonathan Davies

David Cameron has begun his mission to renegotiate the UK's membership with the European Union.

The Prime Minister will outline his plans for reforms at a summit in Latvia.

He said he expects "lots of ups and downs" but wants to give people a "proper choice" in the referendum.

The Conservatives promised an in-out referendum by the end of 2017, although many have called for it to take place sooner.

Mr Cameron said: "You will hear one day that 'this is possible'; the next day something is impossible.

"But one thing through all this will be constant and this is my determination to deliver for the British people a reform of the EU so they get a proper choice in that referendum we will hold before the end of 2017, that will be constant."

The summit in Latvia will not be used for extensive negotiations, but more of an outline of what the Prime Minister wants.

Limiting benefits for migrants is to be high on the agenda, although the EU is generally opposed to the idea - claiming it would go against the freedom of movement rules.