THE SNP's chief whip at Westminster has resigned just six weeks after taking on the position.

Martin Docherty-Hughes has stepped back from the frontbench role citing personal time commitments. 

He is to be replaced by Brendan O'Hara, who had been the party's Westminster spokesperson on international development.

Docherty-Hughes had been made chief whip after Stephen Flynn became the SNP group leader in the London parliament.

His brief time in the position saw controversy after he wrote to MPs in late December to inform them that Patrick Grady, the MP for Glasgow North, had had the SNP whip restored.

Grady had a six-month suspension of party membership imposed on him, and a two-day suspension from the Commons, after he was found to have harassed a staffer.