India has “taken note” of US President Donald Trump’s overnight statement that India would soon know if it would be hit by punitive sanctions stemming from a US domestic law aimed at curtailing arms purchases from Russia, two people familiar with the development said on Thursday.

Trump’s comment followed the signing of a pact last week between India and Russia to buy the S-400 air defense missile system during Russian President Vladimir Putin’s two-day visit to New Delhi.

India’s foreign ministry did not comment on Trump’s remark, made while interacting with reporters in the White House on Wednesday when asked about the $4.5 billion India-Russia deal, when he said: “India is going to find out, aren’t they?”

“You’ll see,” Trump said in response to another question about the timing of his decision. “Sooner than you think,” he added without any mention on whether he would waive the sanctions as has been requested by India.

On 5 October, India signed the pact buying five of the systems that can engage many types of aerial targets such as aircraft, ballistic and cruise missiles, unmanned aerial vehicles—within the range of 400km and up to an altitude of up to 30km. The systems are expected to be deployed along the nearly 4,000-km-long India-China border. China has already acquired the system and news reports say that Moscow has already started the delivery of an unspecified number of the S-400 missile systems to Beijing.

According to the thinking in New Delhi, if Washington does sanction India, it would send out a negative signal vis-a-vis ties that have grown steadily in the past two decades. Coming as it does soon after India and the US signed the Communications Compatibility and Security Agreement—COMCASA—that allows India to procure specialized equipment for encrypted communications for US-origin military platforms, it would be seen as at least slowing the momentum of a particularly important partnership. Many senior US administration officials have described India as a “key pillar” of the Indo-Pacific strategy which aims to form a partnership of countries in the face of the unpredictable rise of China.

Also, sanctioning India would put it in the same category as China with whom the US has a full-blown trade war going and a country that Washington views as a rule-breaker and one that challenges the international system than conforming to it.

Adding to the suspense was the unpredictability of Trump’s temperament. “It’s very well possible that he may exercise his powers for a waiver even after this remark,” said a third person cited above.