The US has gone to great lengths to forge a closer bond with India as Washington seeks partners to push back against China's economic and military rise across the region.

As an example, Indian Defence Minister Nirmala Sitharaman announced plans for the US and India to hold major military drills next year.

The drills would be a first of sorts -- the two countries' forces have not previously trained simultaneously in the air, on the land and at sea.

"We have decided to carry out for the first time a tri-services joint exercise with the United States off the eastern coast of India in 2019," Sitharaman said.

Joining Sitharaman for the talks was Indian Foreign Minister Sushma Swaraj, US Secretary of State Mike Pompeo and Defense Secretary Jim Mattis.

After the summit, Pompeo said it had been "pretty special, historic, a level of relationship that the two countries had not previously had."

Aside from agreeing to joint drills, the two countries also signed a "Communications Compatibility and Security Agreement."

Known as COMCASA, this deal will allow the two countries to exchange sensitive military information quickly and securely.

Despite the friendly tone of the summit, there are plenty of issues India and the US do not see eye-to-eye on.

In 2016, Washington designated India as a "major defence partner", making it easier for the two countries to do arms deals.

India however is finalising a deal with Moscow to buy new systems including its S-400 long-range, surface-to-air missiles.

None of the four officials who spoke to reporters after the summit -- but did not take questions -- mentioned whether the S-400 issue had come up.

Under current US rules, third countries could face sanctions if they transact with Russian defence or intelligence sectors.

If the S-400 deal is finalised, India has signalled it will ask Washington for a special waiver from sanctions, though a US official last week said there is no guarantee it would do so.

The US wants to wean India off Russian systems and onto American hardware. It already has sold US Apache attack helicopters and other gear, and is negotiating to sell armed drones to India.

- Belt and road -

In an apparent reference to China and its Belt and Road initiative -- which floods developing countries with cash for infrastructure projects that sometimes cannot be repaid -- Pompeo said the US and India wish to pursue "fundamental rights and liberties and prevent external economic coercion."

The talks were first meant to be held in April and then in June but both were postponed, triggering speculation of a rift.

After the talks were over, a reporter asked Pompeo if he was involved in a scandal gripping Washington, after the New York Times reported an anonymous editorial penned by a Trump official that depicts the White House in a state of dangerous chaos.

Pompeo denied he had anything to do with the letter.

In May, Trump pulled the US out of the 2015 nuclear deal with Iran and said other countries, including India, must stop buying oil from Tehran before November 4 or face US sanctions.

India however is highly reliant on Iranian crude imports.

India has a $25 billion trade surplus with the United States, and to reduce that the Trump administration is reportedly pressing India to take more US imports.

A draft agreement put forward by Washington last month committed India to accepting more imports of US in the areas of civilian aircraft and natural gas, taking Indian officials by surprise, the Hindu daily reported on Thursday.

"We will consider waivers where appropriate but ... our expectation (is) that the purchases of Iranian crude oil will go to zero from every country or sanctions will be imposed," Pompeo said.

Mattis and Pompeo were due to meet with Indian Prime Minister Narendra Modi later on Thursday.

India and the US also vowed closer cooperation in counterterrorism operations.