Tory MP Steve Brine is being investigated over claims of lobbying the NHS during the Covid crisis while he was chairman of the Commons Health Committee.
The investigation was opened by Parliamentary Commissioner for Standards, Daniel Greenberg, and involves "paid advocacy" and a "declaration of an interest".
Brine allegedly lobbied the NHS Chief Executive to hire anaesthetists through Remedium, a company he had worked for, and received £1,600-a-month for his work as a "strategic adviser".
The probe was prompted by leaked WhatsApp messages from former health secretary Matt Hancock.
While Downing Street refused to comment, some are calling for Brine to step down from his committee role.
Tory MP and former health minister Steve Brine is under investigation by the Parliamentary Commissioner for Standards over allegations of lobbying the NHS on behalf of a recruitment company he was working for as a paid consultant.
Brine allegedly tried to persuade the NHS to hire anaesthetists through the firm Remedium, and received a monthly payment of £1,600.
The investigation involves claims of "paid advocacy" and unclear declarations of interest.
Some politicians have called for Brine to step down from his current role as Chair of the House of Commons Health Committee.
While Downing Street refused to comment, it noted that a parliamentary process was ongoing.