NEW DELHI - India's foreign minister accused Pakistan yesterday of trying to deflect attention from the role of its citizens in last month's terror attack in Mumbai by leaking word of a hoax phone call to the Pakistani president's office that forced its air force to go on high alert.

The episode underscored the high level of tension that remains between the two nuclear-armed nations nearly two weeks after the attack, as India continues to assert that a Pakistani terror group with past ties to the government was responsible and Pakistan insists that it was not involved.

During the call, which came Nov. 28 as the attack was unfolding, the caller allegedly identified himself as Indian Foreign Minister Pranab Mukherjee and threatened to mount military action unless Pakistan moved against the attackers. Pakistani Information Minister Sherry Rehman said in a statement that the call came from "a verified official phone number of the Indian Ministry of External Affairs." The call prompted President Asif Ali Zardari to put the air force on high alert.

News of the call was first reported in the Pakistani newspaper Dawn over the weekend. But yesterday, Mukherjee released a statement saying he had first learned of the call from "third countries," and that the call was a hoax.

"We immediately clarified to those friends, and we also made it clear to the Pakistan authorities, that I had made no such telephone call," Mukherjee said.

Ten gunmen attacked Mumbai on Nov. 26, killing 172 people and wounding 230 in strikes on luxury hotels, a Jewish prayer center, a restaurant, and a train station. Indian officials have said that the gunmen were of Pakistani origin, that they came by boat from Karachi and that they belonged to the Pakistan-based outlawed militant group Lashkar-e-Taiba.

Pakistan has demanded evidence of the Pakistani link, but has also promised to assist New Delhi in the investigation.