Prime Minister Boris Johnson has called off a trip to New Delhi amid surging coronavirus cases in India as the UK keeps a worried eye on a new variant first identified in the vast Asian country.
The UK and Indian governments said on Monday that "in the light of the current coronavirus situation," Johnson will not be able to travel to India next week as planned.
They said Johnson and Indian Prime Minister Narendra Modi would speak later this month and planned to meet in person later this year.
The long-planned trip would have been Johnson's first foreign visit since the start of the coronavirus pandemic more than a year ago.
It was originally scheduled for January but was postponed when infections soared in the UK.
India reported 273,810 new infections on Monday, its highest daily rise since the start of the pandemic.
It has now reported more than 15 million infections, second only to the US.
The Indian health ministry also reported 1619 deaths from COVID-19 in the past 24 hours, pushing the toll to 178,769.
India has the fourth-highest number of deaths after the US, Brazil and Mexico but has a much larger population.
New Delhi, where Johnson and Modi had been due to meet, was placed under a week-long lockdown on Monday as the explosive surge in cases pushed the Indian capital's health system to its limit.
The soaring cases and deaths come just months after India thought it had seen the worst of the pandemic.
Johnson said it was "only sensible" to postpone the trip, given "the shape of the pandemic there".
He said he hoped Modi would be able to come to the UK for the G7 summit in June, to which India has been invited as a guest.
UK health officials are considering whether to add India to a "red list" of countries with high coronavirus rates.
Travellers from those countries are barred in the UK and returning Britons face mandatory hotel quarantines.
The UK has recorded at least 77 cases of a new virus variant that was first identified in India.
Scientists are investigating whether it spreads more rapidly or is more resistant to existing vaccines than the original strain.
The strain, known as B.1.617, is currently designated a "variant under investigation" by British health authorities rather than a "variant of concern," such as those first identified in southeast England, Brazil and South Africa.
Danny Altmann, professor of immunology at Imperial College London, said "my assumption from everything I've seen is that it will become a variant of concern.
"When it becomes a variant of concern, I'd be quite surprised if India wasn't on the red list."
Johnson said the UK's independent Health Security Agency would decide whether to place India on the UK red list.