The probe was set up after the Court of Session in Edinburgh ruled that the Government acted "unlawfully" over the way it handled an internal inquiry into complaints made by two female civil servants against Mr Salmond when he was First Minister.

The Government case collapsed when the Court found it was "tainted" by bias at a potential cost of £500,000 to taxpayers.

Mr Salmond was subsequently charged with a string of sexual offences including attempted rape, but denies any wrongdoing.

Linda Fabiani has written to the Government

Nationalist MSP Linda Fabiani, who is heading up the Scottish Parliament probe, has now written to the Scottish Government stating that their probe will not get underway until the current criminal case against Mr Salmond is disposed of.

But she has warned against ditching any documents which might be of use to the inquiry.

She said: "The Committee wishes to make clear that it expects the Scottish Government to ensure that all hard copy and electronic documents (including emails and electronic messages) which may be relevant to the Committee’s inquiry are preserved," the letter states.

"Documents to be preserved include electronic data which would otherwise be deleted in accordance with a document retention policy or in the ordinary course of business.

"The Committee also expects the Scottish Government to retain details it holds (i.e., names, position, and contact details) of any Scottish Government officials, special advisers or other persons who may have had any involvement whatsoever, directly or indirectly, with, or in connection with, the complaints and actions which are the subject of the Committee’s inquiry."

Salmond inquiry warns Scottish Government against ‘deleting’ evidence