UPDATE 1-UK PM says referendum best solution for EU relations

(Adds detail, background)

BIRMINGHAM, England, Oct 9 (Reuters) - Prime Minister DavidCameron said on Tuesday a referendum on Britain's relationshipwith the European Union was the most sensible way of forging afresh settlement with the 27-member bloc.

Cameron is under mounting pressure from his party's restiveright wing for a vote on Britain's relationship with theEuropean Union. Cameron says Britain should remain in the union.

Cameron gave no time frame for a vote or any indication ofwhat could be asked at such a referendum. The prime minister hassaid he is against a simple in/out referendum.

"When we achieve that fresh settlement it needs consent,either at a referendum or a general election," Cameron told theBBC on the sidelines of the Conservative Party conference in theEnglish city of Birmingham.

"Frankly a referendum is obviously the cleanest, neatest andmost sensible way of doing that," he said.

(Reporting by Mohammed Abbas and Guy Faulconbridge)