A decision is due on Tuesday on whether vice-president Al Gore should be investigated by a special prosecutor over allegations of campaign finance abuses.

At the heart of this controversy lies the allegation that Mr Gore deliberately misled Justice Department officials when questioned about possible campaign finance abuses during the 1996 presidential campaign.

The vice-president has maintained throughout that fundraising calls from his White House office were intended to raise so-called soft money, unlimited contributions which are not allowed to be spent on promoting individual candidates.

But evidence has emerged suggesting that he was also raising hard money, contributions which are subject to stringent financial limits. One condition is that hard money cannot be solicited from federal property.

If Attorney-General Janet Reno decides to appoint an independent prosecutor, it could open the way for a much wider investigation into allegations that President Clinton was also in breach of campaign finance regulations.