Bangladesh's highest court on Tuesday upheld the death sentence against the second highest ranked Islamist leader for war crimes during the country's battle for independence, paving the way for his hanging.

In a brief ruling, Chief Justice S.K. Sinha "dismissed" Ali Ahsan Mohammad Mujahid's appeal against his sentence, an AFP correspondent at the Supreme Court said.

"The death penalty handed down to him has been upheld," prosecutor Soumya Reza told AFP, adding Mujahid could be hanged within months.

Mujahid, general secretary of Bangladesh's largest Islamist party, Jamaat-e-Islami, was found guilty in 2013 of five charges including murder and torture, a ruling that sparked deadly nationwide protests by his supporters.

The 67-year-old leader now faces the gallows for his role in Bangladesh's war of independence in 1971 unless the case is reviewed again by the same court or he is granted clemency by the country's president.

In the past, the Supreme Court has swiftly dismissed such reviews of two other senior Jamaat officials, leading to their execution, the latest in April this year. They also declined to seek clemency from the president.

Mujahid was found guilty of being the chief commander of Al Badr, a notorious pro-Pakistani militia that carried out the "extermination of intellectuals" including top Bangladeshi writers, journalists and professors towards the end of the war against Pakistan.

When it became clear that Pakistan was losing the war, dozens of intellectuals were abducted from their homes and murdered in December 1971 in the most gruesome chapter of the nine-month conflict.

Their bodies were found blindfolded with their hands tied and dumped in a marsh on the outskirts of the capital.

Mujahid's lawyers claimed that his name was not in the list of Al Badr commanders or activists that was published by the post-independence government.   

"We'll seek a review of the Supreme Court judgement," defence lawyer Shishir Manir told AFP.