The US is opposed to India's purchase of the S400 Triumf missile and earlier slapped sanctions on nations like China for making deals with Russia. India has suggested the US offer a waiver, pointing to a new US law crafted for this purpose. The law though, is yet to be signed off by President Donald Trump.

The US has suggested that India look for alternatives to the S400 Triumf missile, citing a law that imposes sanctions on any country that has "significant transactions" with Iran, North Korea or Russia.

The two nations also have differences over President Trump's ending trade concessions for India on June 1. New Delhi, in retaliation, imposed retaliatory tariffs on 28 US items earlier this month.

Hours after Mr Pompeo landed in New Delhi last night, the US said it wants PM Modi to lower trade barriers and embrace fair and reciprocal trade

Mr Pompeo today said, "The US wants greater market access. We've got to get the economic piece right". Mr Jaishankar said he has "pushed for a constructive and pragmatic view", and the "real test of our intentions will be our ability to deal with this".

On the purchase of oil from Iran too, the two nations have differences. Amid tension with Iran, US is pushing for a boycott of Iran's oil. Today, Mr Pompeo said Iran was the "biggest sponsor of terror". In the evening, Mr Pompeo, during a policy speech, said India has made "hard choices: to cut off oil imports from Iran and that the US is "doing everything" to ensure crude oil imports to New Delhi.

India traditionally buys much of its oil from Iran. Currently the emergency crude reserves are at 39.1 million barrels, which can run for just 9.5 days. Oil companies have stopped imports from Iran to avoid sanctions.

The US and Iran have been locked in an escalating war of words since the downing of a US surveillance drone in May. President Trump pulled back from plans to retaliate with military strikes, saying the response -- and the collateral damage -- would not be "proportionate". But after another round of US sanctions, Iran said the door to diplomacy was now "shut forever".

Asserting that the world is worse off when religious rights are compromised, Mike Pompeo on Wednesday evening called for speaking "strongly" in favour of religious freedom. The comment is likely to raise eyebrows, coming on the heels of a US State Department report on the matter that was critical of India on that score.