The UK's talks with Spain over an end the centuries old dispute over Gibraltar have not "run into the sand", the British foreign secretary has insisted.

Under close questioning from a powerful committee of MPs, Mr Straw said the talks over sharing sovereignty of the colony continued.

You can't anticipate the outcome of negotiations until they are complete

Jack Straw Foreign Secretary

But he was not a "soothsayer" and could not say whether an agreement - which would go to a referendum of Gibraltar residents - would be reached.

Mr Straw's comments come after Europe Minister Peter Hain this week admitted a deal with Spain might not be reached before the summer deadline.

No predications

It might be a "while yet" before any agreement was reached, said Mr Hain.

Donald Anderson, chairing the Commons foreign affairs select committee, said there was a growing consensus among observers that the talks had now "run into the sand".

Mr Straw denied this, saying: "You cannot anticipate the outcome of negotiations until the negotiations are complete."

Donald Anderson asked about the chances of Gibraltar saying 'yes'

Critics of the talks process argue Spain would only see a joint sovereignty deal as a staging post on the way to sole control over the Rock.

The foreign secretary said the UK had always ruled out giving Spain full sovereignty and only Spanish ministers could say how they viewed the issue.

Talks on the dispute will continue next Wednesday between the UK minister and his Spanish counterpart, Josep Pique.

Referendum chances

Gibraltarians heckled and jeered Mr Straw in a recent visit to the Rock and Mr Anderson asked whether he seriously thought there was residents would ever accept a sovereignty deal in a referendum.

Mr Straw argued there were circumstances the residents would strongly benefit from a deal.

Progress could be made in the second stage of the process - where an agreement reached between the UK and Spain was debated, he suggested.

It was possible Gibraltarians would decide a deal would give them more power over their own lives, as well as solving daily problems with Spain over issues like border delays, added Mr Straw.

He denied suggestions that those problems caused by Spain could get worse than they were before the talks if no agreement was reached.