An SNP MP has resigned his party membership amid a police investigation into sexual harassment allegations.

It means Patrick Grady will no longer be an SNP MP for Glasgow North and will sit as an independent.

The Metropolitan Police confirmed it is investigating an incident which took place at a London pub in 2016.

A parliamentary probe saw Mr Grady suspended from Westminster for two days after he was found to have acted inappropriately towards a male SNP staff member.

Mr Grady, the SNP’s former chief whip, said he was “profoundly sorry” after the independent panel’s investigation.

Ian BlackfordSNP Westminster leader Ian Blackford was heard in a leaked recording to encourage party MPs to rally round Mr Grady (House of Commons/PA)

SNP Westminster leader Ian Blackford had urged Mr Grady to consider his position after criticism of the party’s handling of the complaint.

That came after Mr Blackford was heard in a leaked recording to tell SNP MPs to rally round Mr Grady, saying he looked forward to “welcoming Patrick back” following his two-day suspension.

A Metropolitan Police spokesperson confirmed inquiries are ongoing.

He added: “On Wednesday June 22, police received an allegation of sexual assault that is said to have taken place in October 2016 at a commercial premises in Folgate Street, E1.

“The report was submitted online by a third party.

“Officers will now be making inquiries, including contacting the alleged victim, in order to assess what further action is required.”

An SNP spokesman said: “Patrick Grady is stepping away from his party membership while the police inquiry continues.”

Scottish Conservative chairman Craig Hoy said: “Patrick Grady should have been sacked long before this but the SNP have shown they have absolutely no backbone and would rather back the perpetrator over the victim.

“The abuser is gone but the poison remains in the SNP and the party leadership should be ashamed of the way they have handled this scandal.

“It’s appalling that Nicola Sturgeon and Ian Blackford are still treating a disgraced MP with more sympathy than the victim who suffered sexual harassment.

“Bullying Blackford must now face the repercussions he deserves and be sacked so victims have confidence that they’ll be taken seriously in the future.”

Scottish Liberal Democrat leader Alex Cole-Hamilton has called on Mr Blackford to resign.

He said: “At no point has Ian Blackford showed an ounce of leadership. He voiced absolute full support for Patrick Grady over the victim, allowed SNP whips to act menacingly and resorted to intimidation.

“Ian Blackford must go.”