Verdicts on whether former Cabinet ministers Jack Straw and Sir Malcolm Rifkind broke lobbying rules could be delayed - because no MPs have been appointed to the Commons standards watchdog.
Parliamentary standards commissioner Kathryn Hudson delivered her reports into the ex-MPs, who were caught up in a sting by the Daily Telegraph and Channel 4's Dispatches, last week.
They should now be considered by the cross-party Standards Committee. However, while Labour's Kevin Barron was re-elected as chairman in June, the committee does not technically exist yet because no other politicians have been chosen to join him.
Nominations are usually agreed between parties, and then have to be put to the Commons by Leader of the House Chris Grayling for approval.
Four months after the general election, no names have been proposed.
The delay is said to be partly due to tensions over the political balance on the committee, which was reformed recently to include seven MPs and up to seven lay members.
Aides to Mr Grayling said they were expecting to table the motion "soon". The delay means it is unlikely the reports on Mr Straw and Sir Malcolm will be finalised until mid-October, after the recess for party conferences.
It emerged in February that Sir Malcolm had been filmed telling undercover reporters he could arrange "useful access" to every British ambassador in the world because of his status.
He denied any wrongdoing, but stepped down as head of the powerful Intelligence and Security Committee and did not stand again as a Tory MP.
Mr Straw, who had already announced he was quitting the Commons before the sting, was accused of taking a job with a firm that won a £75 million government contract after he privately lobbied a minister on its behalf.
Alongside alleged lobbying rule breaches, Ms Hudson has been looking at whether the former Labour Foreign Secretary misused parliamentary resources and failed to declare interests.
There have been reports that Mr Straw, who has also denied wrongdoing, was overlooked for a peerage in the recent dissolution honours list because of the ongoing probe. But he has been appointed by the government to a controversial panel reviewing the operation of the Freedom of Information Act.
The standards committee has limited options for punishing Mr Straw and Sir Malcolm if they are found to have broken rules, as they are no longer MPs.
However, both have been granted parliamentary passes giving them access to the estate as former members, which could potentially be withdrawn.