In rejecting the appeal by Abdel Quader Molla, a five-member panel of the Bangladesh Supreme Court sided with the prosecutor's demand for the death penalty, The Wall Street Journal reported Tuesday.
Molla, a leader of the opposition party Jamaat-e-Islami, was found guilty Feb. 5 by a war crimes tribunal of crimes against humanity during the country's war of independence in 1971.
Opposition groups charge Prime Minister Sheikh Hasina is using the tribunal to get rid of political rivals. The tribunal has indicted 11 men, all of whom are opposition politicians. Nine of them are members of Jamaat-e-Islami.
All six found guilty so far are Jamaat-e-Islami members.
Hasina's supporters deny there has been any interference in the trials.
The trials have divided the country. About 120 people have died in street protests by Islamist groups, rights groups say. The government says the death toll has been lower.
After Molla's conviction in February, the government retroactively changed the law, allowing prosecutors to seek the death penalty on appeal.