The White House has admitted that many more officials are implicated in the scandal over misuse of political email systems for party political purposes.

A White House spokesman had stated that only a handful of people were using Republican Party email accounts to conduct government business, but the number has now risen to 88.

Over 50 of these have no email records at all and there are only 130 emails from Karl Rove during President Bush's first term and none before November 2003.

The Presidential Records Act requires the recording of any communication used in governing, but officials bypassed this by using email accounts set up and run by the Republican Party.

The legislation requires the president to 'take all such steps as may be necessary to assure that the activities, deliberations, decisions and policies that reflect the performance of his constitutional, statutory or other official or ceremonial duties are adequately documented ... and maintained as presidential records'.

The Committee on Oversight and Government Reform for the US Congress said: " The evidence obtained by the Committee indicates that White House officials used their Republican National Committee [RNC] email accounts in a manner that circumvented these requirements.

"At this point in the investigation it is not possible to determine precisely how many presidential records may have been destroyed by the RNC.

"Given the heavy reliance by White House officials on RNC email accounts, the high rank of the White House officials involved and the large quantity of missing emails, the potential violation of the Presidential Records Act may be extensive."

White House spokesman Tony Snow said: "This is an administration that is very careful about obeying the law.

"We take it seriously. The White House legal counsel's office takes it seriously. And we will look at whatever requests for information people on the Hill may have to offer."