David Cameron has said that MPs being paid to lobby is "not acceptable" adding that it was right that Jack Straw and Malcolm Rifkind have referred themselves to the Parliamentary Commissioner,
Speaking in Hastings, the Prime Minister said: "...I think it's also right that in both cases, while that happens, the party whip should be suspended. That is what will happen with Sir Malcolm Rifkind as well as with Jack Straw.
"In Sir Malcolm's case, he is still a candidate at the next election, so there will be an immediate disciplinary inquiry by the Conservative Party to look at this case."
MPs reject proposals for a ban on politicians holding paid directorships, consultancies or trade union roles.
Sir Malcolm Rifkind is to quit as an MP at the general election amid fresh pressure over cash for access allegations.