BBC Correspondent Bridget Kendall says the Starr investigation is hotting up

The reports have not been confirmed by either side but, if correct, it is the first direct contact between the two sides since January.

Mr Starr is investigating whether the president had an affair with Ms Lewinsky - a former White House intern - and then urged her to lie under oath to deny the alleged relationship.

One report said no decision had been made on whether Miss Lewinsky would be offered immunity from prosecution in return for her testifying to the grand jury investigating the claims.

Negotiations over testimony

BBC correspondents say the investigation appears to be reaching a crucial stage as last week Mr Starr issued a subpoena summoning Mr Clinton to give evidence.

Lindsay: lost battle to stay silent

The president - who denies having an affair with Miss Lewinsky and asking her to lie about it - has indicated that he does not want to give evidence directly to the grand jury.

However, Mr Clinton is reluctant to defy the subpoena outright. Our correspondents say his staff are negotiating for him to be allowed to testify at the White House or on video tape.

One report says that the president wants to wait until September when he gets back from visits to Russia and Northern Ireland.

Our correspondents says if Mr Starr hears evidence from Mr Clinton and Ms Lewinsky, the last major pieces of the jigsaw will be in place, and he can then write his report for Congress. But that could take many weeks yet.

The Clinton team suffered another legal setback on Monday.