Gordon Brown has raised concerns about the investigation into Madeleine McCann's disappearance with his Portuguese counterpart.

Mr Brown discussed the police inquiry with the premier Jose Socrates during private talks in Lisbon, where the pair are attending the EU summit.

Mr Brown said he wanted to be assured "that the police authorities are taking the actions that are necessary and there's proper cooperation between the British and Portuguese police".

The pair previously discussed the case in July, when Mr Socrates assured Mr Brown "everything possible" was being done to find the missing four-year-old.

Mr Brown's involvement in the case has sparked resentment in Portugal in the past.

One detective accused parents Gerry and Kate McCann of creating "constant interruptions and distractions" after it emerged they had been keeping him personally updated on developments over Madeleine, who went missing in the Algarve resort of Praia da Luz on May 3.

The policeman said: "It is amazing to me that people in high positions are getting involved. I can't think of any case in Portugal where this has happened."

A source in the Portugese police admitted yesterday they have no evidence against the McCanns, who are still official suspects.

A high-ranking detective in the investigation told the Portuguese newspaper 24 Horas: "The truth is, nothing which allows us to make a definite accusation against the McCanns has yet emerged."

It also emerged yesterday that Mrs McCann is having haunting visions of Madeleine at night.

Her mother Susan Healey said: "She told me she was unable to sleep a couple of nights ago and I said, 'Did the twins wake you up?' She said, 'No, Madeleine came'."