ISLAMABAD — Pakistan’s top court ordered the arrest of the country’s prime minister in a corruption case Tuesday, officials said, as a firebrand cleric rallied thousands of people against the government for a second day in the capital.

The Supreme Court’s order, which is likely to inflame the already antagonistic relationship between the government and the court, was related to a case involving private power stations set up to provide electricity to energy-starved Pakistan. The judges are investigating allegations that the bidding process was marred by corruption.