A team of officials from the FBI and US Department of Justice currently in India will travel to Pakistan to follow up on leads about LeT operative David Coleman Headley's activities there.
The team, which briefed Indian officials on Monday in New Delhi, will travel to Pakistan, State Department spokesman Ian Kelly said.
"After the meetings in New Delhi, this team of the Department of Justice and the FBI will travel directly to Islamabad to brief appropriate Pakistani security officials. We're also working with Pakistani officials to follow up on leads regarding Headley's activities in Pakistan," he said.
Kelly said the FBI has been consulting closely with Pakistani authorities on this case, following the practices developed in previous high-profile counter-terrorism investigations.
Headley was on Monday charged with planning the Mumbai attacks that killed 166 people, including foreigners.
The visit of the FBI team shows the commitment of President Barack Obama on the case, he said.
"This visit reflects the President's commitment to Indian Prime Minister Manmohan Singh during his recent visit to cooperate closely on the case," he said.
During last month's State visit of Singh, Obama had discussed the issue with the Indian leader and had promised full US support in sharing the results of the FBI investigations.