Democratic Unionist MP Ian Paisley is facing a 30-day suspension from the House of Commons after his failure to register two family holidays paid for by the Sri Lankan government.
Mr Paisley had already apologised for what he said was his "unintentional failure" to register the hospitality, which he estimated was worth £50,000 (€56,000).
The sanction recommended by a parliamentary watchdog yesterday could see Mr Paisley face a by-election.
MPs who are suspended for more than 10 days are open to a recall petition.
A by-election would be triggered if 10pc of the electorate in Mr Paisley's North Antrim constituency sign that petition.
If rubber stamped by Parliament, the suspension will also mean prime minister Theresa May will lose of one of the 10 DUP MPs propping up her minority government during a period that could see a number of crucial Brexit votes.
The sanction was outlined by the House of Commons Standards Committee following receipt of the findings of an investigation by the Parliamentary Commissioner for Standards.
The committee said Mr Paisley, son of the late DUP founder the Rev Ian Paisley, had committed "serious misconduct" and his actions "were of a nature to bring the House of Commons into disrepute".
The report, which said the cost of the hospitality may have been "significantly more" than Mr Paisley's £50,000 estimate, said the Sri Lankan holidays in 2013 included business-class air travel, accommodation at first-class hotels, helicopter trips and visits to tourist attractions for the MP and his wider family.
The trips also included meeting with Sri Lankan governmental figures.
The threshold for registering such hospitality in 2013 was around £660 (€740).
In 2014, Mr Paisley wrote to then prime minister David Cameron to lobby against a proposed United Nations resolution setting up an international investigation into alleged human rights abuses in Sri Lanka.
Mr Paisley is due to address the Commons today.