David Cameron is holding new talks with fellow European leaders as he continues to try to build support for his renegotiation of Britain's EU membership terms.
Arriving in Brussels for a summit of European, Latin American and Caribbean nations, the Prime Minister said he was "content" with progress so far.
Mr Cameron was meeting with Cypriot president Nicos Anastasiades in the margins of the summit with further talks expected tomorrow with leaders from Spain, Belgium, Finland and Romania.
It follows his whistle-stop tour of key European capitals - including Berlin, Paris and Warsaw - in which he sought to spell out what he wanted to achieve from the re-negotiation ahead of the promised in/out referendum on Britain's continued membership.
The latest talks come after the European Referendum Bill - requiring the vote to be held before the end of 2017 - cleared its first Commons hurdle last night, receiving its second reading from MPs with a majority of 491.
"That reform and re-negotiation, it's under way, I'm content with the progress we've made so far but the referendum will happen by the end of 2017," Mr Cameron told reporters in Brussels.
"It was historic last night that we had the second reading of the Referendum Bill. It will be the British people that make this decision."
Earlier, at Prime Minister's Questions, Mr Cameron defended provisions in the bill to scrap the usual "purdah" restrictions governing the use of the Whitehall machine in the "short campaign" in the run-up to the referendum.
Eurosceptics, including former cabinet minister Owen Paterson, have claimed the Government could use the relaxation of the rules try to "fix" the result.
However Mr Cameron told MPs: "When the negotiation is complete and the Government has a clear view, I don't want us to be neutral on this issue, I want us to speak clearly and frankly on this issue.
"When it came to the Scottish referendum, I actually felt in the last few weeks before the referendum the UK government was often being advised it couldn't take a view on the future of the UK."
"I think that was a ridiculous situation, which is why we have put forward the change to the purdah rules."