Google CEO Sundar Pichai has promised changes to the tech giant's sexual harassment policies, a week after thousands of its employees across the world, including in India, walked out in protest against the company reportedly shielding some top executives accused of sexual misconduct.

In a memo to employees on Thursday, the Indian-origin CEO said, "We recognise that we have not always gotten everything right in the past and we are sincerely sorry for that. It's clear we need to make some changes."