The deal would still require approval by Congress. California-based General Atomics, the maker of the Guardian drone sought by India, declined to comment.
Prime Minister Narendra Modi on Saturday arrived in Lisbon on the first leg of his three-nation tour during which he will hold talks with his Portuguese counterpart Antonio Costa to boost bilateral ties.
So far in his presidency, Trump has focused on outreach to China, India's strategic rival, as he looks to Beijing to rein in North Korea.
"We are also interested in continuing our cooperation with Pakistan", the official said adding that the United States is concerned about tensions between India and Pakistan.More news: YouTube sees 1.5 bln logged in viewers per month
The Indian navy wants the unarmed surveillance drones to keep watch over the Indian Ocean. Received by Foreign Minister Augusto Santos Silva at the Lisbon airport, PM Modi is now on the first leg of his three nation tour.
The official said that the PM trip is an opportunity to strengthen the US-India strategic partnership, which is a critical partnership in promoting the stability and security in not only Pacific Asia but also globally.
Given Goa's strong cultural and historic connection with Portugal, Modi's visit, the first leg of his three-nation tour that will also take him to the USA and the Netherlands, is significant. In that, he's likely to find common ground with Trump.
"Ultimately, that's the ultimate goal", the White House official said.
For personality polarities aside, there is every reason to expect positive chemistry between the rigorously disciplined Prime Minister and the irrepressible President on their first meeting-and out of that chemistry can come mutual benefits to India and the United States.More news: The best 'Call of Duty' game ever is coming to PlayStation 4
But there could be increased strains on trade issues.
India and Portugal also agreed to cooperate in fighting terrorism and violent extremism, and also to set up a joint science and technology fund of four million euros, PM Modi said.
The country's foreign minister, Sushma Swaraj, later dismissed Trump's remarks as "completely not true", and Modi has made it clear during recent meetings with European leaders that the country will stay the course on its commitment with or without the United States.
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