Prime Minister Manmohan Singh spoke to United States President Barack Obama on Monday evening against the backdrop of tumultuous developments in the region, including the killing of al-Qaeda leader Osama bin Laden in neighbouring Pakistan and the continuing unrest in West Asia and North Africa.

The day also marked the beginning of the third round of the China-U.S. Strategic and Economic Dialogue.

“It was a warm conversation which covered wide-ranging subjects. They discussed further growth and development of India-U.S. relations, and the developments in the region,” official sources said.

The two leaders spoke at a time when both U.S. companies in the race missed out on a lucrative Indian Air Force tender for fighter aircraft and the entry of American companies in the Indian nuclear power-based electricity sector due to the Nuclear Liability Act.

On the other hand, India needs a helping hand from the U.S. to gain membership in four non-proliferation organisations, including the Nuclear Suppliers' Group. It is also negotiating with the U.S. to benefit from the easing of curbs on export of high-end technology.

Both countries are concerned about the situation in the Arab world, the main source of their petroleum supplies, and are interested in a political solution in Afghanistan that marginalises groups espousing militant ideology.

Narayan Lakshman reports from Washington:

The White House today confirmed that United States President Barack Obama had spoken to Indian Prime Minister Manmohan Singh, touching upon the “the successful American action against Osama Bin Laden.” It was their first call since the killing of Osama on Sunday, May 1.

The two leaders also took the opportunity to go over key bilateral issues, including reviewing progress in implementing the many crosscutting initiatives launched during Mr. Obama’s historic visit to India last November.

While the second round of the Strategic Dialogue that was initially slated for the spring of 2011 stands postponed due to elections in Indian states, the President and Prime Minister were said to have talked spoken about the wide-ranging, minister-level talks.

In a statement the White House said, the two leaders re-affirmed their commitment to building a global, strategic partnership, including defence cooperation, and looked forward to the upcoming meetings of the Strategic Dialogue, the Homeland Security Dialogue, the Joint Space Working Group, and the High-Technology Cooperation Group.”

The Homeland Security Dialogue assumes particular significance for in the wake of the Mumbai terror attacks of 2008. In 2010 Home Minister Palaniappan Chidambaram had visited the U.S. and interacted with different divisions of the U.S. homeland security apparatus, focusing on issues such as megacity policing.

The Joint Space Working Group and the High-Technology Cooperation Group are also key components of the bilateral relationship and last year played an important role in seeing through policy reforms in areas such as the U.S. Entities List for export control restrictions.

Following numerous rounds of consultations through these and other groups Mr. Obama’s visit last year saw the removal of institutions such as the Indian Space Research Organisation from the restricted list.