Boris Johnson has announced a set of investment and export deals with India as he makes a two-day trip to the country.
He is due to discuss trade and security ties with his counterpart Narendra Modi in India's capital New Delhi on Friday.
Meanwhile in Westminster, MPs are debating whether to investigate Mr Johnson over lockdown parties held in No 10.
They will vote on whether to open a probe into whether the PM misled MPs.
Mr Johnson arrived in Gujarat, India's fifth-largest state, on Thursday. his first major trip to the country as PM after previous visits were postponed because of Covid.
He was presented with a copy of a guide to London written by Mahatma Gandhi on a visit to Sabarmati Ashram - the centre of the peace leader's campaign against British rule.
He also draped a ring of khadi cloth around a statue of Gandhi before signing a guestbook, writing it was an "immense privilege" to learn about how he "mobilised such simple principles of truth and non-violence to change the world for the better".
However, the PM's praise for Gandhi did not extend to his vegetarian diet - revealing on the plane his own favourite curry was a lamb rogan josh.
'Deepen our friendship'
The deals Mr Johnson announced will be across industries, from software engineering to healthcare, as well as a collaboration on satellite launches.
It is claimed they will be worth £1bn to the British economy, promising 11,000 jobs in the UK as a result.
Speaking to reporters on a visit to a JCB plant in Vadodara, owned by Tory Lord Bamford, the PM said it was "an absolutely amazing example of the synergy [and] the synthesis between UK technology and Indian technology".
He added: "The opportunity for us to deepen our friendship [with India] and our ties is enormous."
The prime minister will also use the visit to push for a post-Brexit free trade deal with India, with a fresh round of negotiations set to begin in the country next week. He said he hoped it would be signed "by the autumn".
But difficult conversations on the invasion of Ukraine are also likely, given India's strong ties with Russia.
The country has not criticised Russia directly since it invaded and did not join the condemnation during a United Nations vote on the issue.
The UK has been trying to persuade India to reduce its reliance on Russia, with Foreign Secretary Liz Truss travelling to the country last month for talks.
The PM told reporters he had already raised the issue of Ukraine with Prime Minister Modi, but he said the country had condemned the "atrocities" in Bucha.
He added: "As I think everybody understands, India and Russia have historically a very different relationship than perhaps Russia and the UK have had over the last couple of decades, we have to reflect that reality.
"But clearly I will be talking about it to Narendra Modi."
On the plane to India, Boris Johnson parried away questions about parties.
Asked if there were any circumstances he would consider resigning if he got more fines, Mr Johnson said he wasn't going to speculate - but insisted he would fight the next election.
He said politicians were better off focusing on things that mattered to voters, rather than talking about themselves.
Of course, the slow burning fuse of the Met's investigation and the eventual publication of Sue Gray's report into Downing Street parties could plunge his premiership into crisis once again.
But Boris Johnson hopes this trip will show him getting on with business.
A free trade deal with India will not be signed on this visit, but Mr Johnson said the UK was aiming for one by the end of the year.
But difficult conversations are likely on Ukraine.
The prime minister was also very downbeat on the prospects of a negotiated end to the crisis given what he called President Putin's manifest lack of good faith.
The visit comes as Mr Johnson continues to face pressure at home over lockdown parties in No 10 during the pandemic.
Last week, he, his wife and Chancellor Rishi Sunak received fines from the police for attending a birthday party thrown for him in the Cabinet Room in June 2020.
The PM repeatedly apologised to the Commons on Tuesday for what he called his "mistake" and has denied misleading the House, despite previously telling MPs that no Covid laws were broken in Downing Street.
But Labour leader Sir Keir Starmer branded his statement as "a joke", while both the SNP and Liberal Democrats reiterated calls for him to resign.
Mr Johnson could receive more fines over lockdown parties, having attended at least two more events under investigation by the Met, and having been reported to have been at three more.
But the PM said he preferred to focus on "the things that make a real difference" to the public rather than "politicians themselves".