(CNN)Boris Johnson, who until recently was the UK's foreign secretary, is facing an investigation into potential breaches of the Conservative Party's code of conduct, CNN understands.
The party is understood to have received a number of complaints after Johnson likened Muslim women who choose to wear veils to "bank robbers" and "letter boxes" in a newspaper column earlier this week.
The comments were made in Johnson's weekly column for Britain's Daily Telegraph newspaper, in which he was criticizing Denmark's recent implementation of a burqa ban.
An independent panel will be convened to review the complaints.
A spokesperson for the governing Conservative Party said in an emailed statement: "The code of conduct process is strictly confidential."
Johnson has come under increasing pressure in recent days and was asked to apologize for his remarks by Brandon Lewis, the chairman of the Conservative Party.
On Tuesday, Prime Minister Theresa May joined the growing chorus of lawmakers publicly rebuking Johnson over his choice of language.
"It's not language I would have used and I think he was wrong to have used that language, and I agree with Brandon Lewis," May said.
Johnson was a contentious figure in May's cabinet before he unceremoniously resigned last month over the state of Brexit negotiations.
In his resignation letter, Johnson said the Brexit "dream is dying, suffocated by needless self-doubt," before sharply criticizing May's strategy for a departure from the bloc.
If an investigation does conclude that Johnson has breached the party's code of conduct, the party could opt to disassociate itself from him in an action known as having the whip withdrawn. It means he could effectively be expelled from the party though he would keep his seat in Parliament.
However, many would consider such a move unlikely and something of an extreme method of disciplining a party member.
