The first two-plus-two dialogue between India and the US has been postponed for now due to uncertainty over the confirmation of Mike Pompeo as President Donald Trump's new Secretary of State, according to an official.

The two-day dialogue, announced last summer when Prime Minister Narendra Modi had a successful meeting with President Trump at the White House, was tentatively scheduled for April 18-19.

"It has been postponed for now," an informed US official said.

The official wishing anonymity, however, quickly pointed out that it would have no impact on the bilateral relationship as the meetings this week by the foreign and defence secretaries decided to continue with their agenda.

There was no official announcement of the high-level dialogue involving the foreign and defence ministers from the two countries.

India's foreign and defence secretaries were here early this week for preparatory talks with their American counterparts.

The Indian delegation landed in Washington DC amidst the firing of Rex Tillerson as the Secretary of State by Trump.

The delegation continued with their meetings both at the State Department and at the Pentagon as scheduled, during which it was decided to hold the dialogue at a later date, which appears unlikely before the summer.

The dialogue was seen as a vehicle to elevate the strategic relationship between the two countries.

After June last year, the two countries have tried at several other dates for the dialogue to take place, including sometime in November and December.

Officials also checked for a time in January this year, but both sides were having a tough time in finding a day when all the four leaders - External Affairs Minister Sushma Swaraj, Defence Minister Nirmala Sitharaman from India and Defence Secretary Jim Mattis and the fired Secretary of State Rex Tillerson, would be available.

It was finally in February this year that two days in mid-April was zeroed in for the talks.

However, the plans had to be scuttled as on March 13 Trump announced that Tillerson had been fired and nominated Pompeo, who is currently the CIA director, to replace him as the Secretary of State.

Pompeo needs to be confirmed by the Senate. Spring recess of the Congress begins on March 22 and lawmakers would resume their legislative business on April 2. The Senate Foreign Relations Committee, which hold the confirmation hearing, has not scheduled it on its calendar yet.

Once Pompeo's nomination process breezes through this committee, then it would go to the Senate floor for a vote.

Given the sharp differences between the Republicans and the Democrats in the Senate, officials decided not to take any chance by going ahead with the mid-April date for the two-plus-two talks.

The new dates will now be determined after Pompeo occupies the Foggy Bottom headquarters of the State Department and settles down as the top American diplomat.