ISLAMABAD, Pakistan — The Pakistani government and opposition on Thursday united in criticism of a newly announced $10 million American bounty for Hafiz Saeed, a militant leader accused of orchestrating the 2008 attacks in Mumbai, India, during a heated session of Parliament in which lawmakers demanded that Washington provide proof of Mr. Saeed’s terrorist credentials.

Prime Minister Yousaf Raza Gilani warned that the American reward, which was announced by a senior State Department official in India on Monday, was a “negative message” and would “further widen the trust deficit” between the two countries.

Parliament is in the throes of a contentious debate about ties with the United States, which have been virtually frozen since American warplanes killed 24 Pakistani soldiers during a disputed border clash in November. Now, it seems, Mr. Saeed’s fate may present a new hurdle.

Opposition lawmakers said the American offer of $10 million for information leading to the capture or arrest of Mr. Saeed, who is accused of leading the militant group Lashkar-e-Taiba and who lives openly in the eastern city of Lahore, was “mind boggling” and “ridiculous.”