Boucher's two-day trip to India starting Tuesday comes as India has ended its latest round of talks on a safeguard agreement with the U.N. nuclear watchdog, the International Atomic Energy Agency, the Press Trust of India reported.

Implementation of the civil nuclear deal, however, remains stalled because of opposition from the Left parties in India's ruling coalition. Some U.S. lawmakers also oppose the agreement.

Boucher is in charge of South Asia in the U.S. State Department. India must get the safeguard agreement with the IAEA before the deal can become operational.

The PTI report said both the IAEA and India reportedly made "considerable progress" in the latest talks. Boucher would review the progress at those talks.

India also must get a waiver from the 47-member Nuclear Suppliers Group allowing it to have civil nuclear cooperation with the international community.

The United States reportedly is urging India to get the steps completed as early as possible so the agreement can be placed before U.S. Congress for ratification by May, the PTI report said. It is feared any delay beyond that could kill the agreement.