Bangladesh's Supreme Court has upheld the death sentence for a top leader of an Islamist party for war crimes and crimes against humanity during the country's independence war against Pakistan in 1971.

On Tuesday, a four-member panel headed by the country's chief justice dismissed the appeal by Jamaat-e-Islami party's Secretary General Ali Ahsan Mohammad Mojaheed against a 2013 verdict sentencing him to death.

Mojaheed was convicted in 2013 of five charges including murder, abduction and torture.

The 65-year-old will be hanged if the case is not reviewed by the same court or if he doesn't get a presidential clemency.

Bangladesh says Pakistani soldiers, aided by local collaborators like Mojaheed, killed about 3 million people and raped 200,000 women in 1971.