Bangladesh's Supreme Court has upheld the death sentence for an influential opposition leader and an aide to a former prime minister for his role in mass killings during the country's independence war against Pakistan in 1971.

Chief Justice S.K. Sinha delivered the verdict Wednesday against Bangladesh Nationalist Party leader Salauddin Quader Chowdhury, a former aide to ex-Prime Minister Khaleda Zia.

The ruling clears the way for the man's execution unless he gets presidential clemency.

Bangladesh says Pakistani soldiers, aided by local collaborators, killed 3 million people and raped 200,000 women during the nine-month war that ended in December 1971. Prime Minister Sheikh Hasina set up the tribunal in 2010.