British travellers in Australia and New Zealand are calling for help to get home - as travel lockdowns mean hardly any normal flights remain.
In New Zealand, international travel is closing down - sparking panic among British visitors who fear they are stranded.
Some of the affected have told the BBC they feel they've been "abandoned" after struggling to get official help.
Many have urged the UK government to send chartered flights.
The travellers' problems have been compounded by Singapore - a common transit point - closing its borders to all visitors.
New Zealand will enter a full lockdown from the end of Wednesday, when only essential services will be open.
UK officials in the nation told the BBC they are "in touch daily" with the travel industry. On Tuesday, they advised British people to register their details online.
"We recognise how stressful this situation is to the Brits who have had their New Zealand plans upended by this pandemic," said the Foreign and Commonwealth Office (FCO).
Who is stuck?
According to an online database started by a British woman in New Zealand and viewed by the BBC, more than 1,000 British nationals have registered for help, with the majority in Auckland and Christchurch.
Lara Suleyman, from Kent, started the list on Monday, after sharing a plea on Facebook to connect with other stranded citizens.
She told the BBC she has since been contacted by holiday makers, backpackers, students, those on longer-term work visas and many more.
"I've heard from doctors who are keen to get back to the NHS to help out their colleagues, tourists facing eviction from their hotel rooms, as well as pretty unwell cancer patients who are running low on their medicine and can't get through to the UK Consulate," she said.
The situation is more alarming in New Zealand than Australia she says, because the nation is due to plunge into a rigorous lockdown.
On Tuesday, Australia announced it would extend its transit window for international passengers coming from New Zealand to 12:00 local time on 26 March.
Why can't they get out?
With border restrictions announced in Australia, New Zealand and Singapore in the past week, commercial airlines had already begun cancelling flights and announcing end dates for routes.
In New Zealand, those affected say it has become almost impossible to find a flight, while in Australia seats have become highly limited and increasingly restricted to business class.
Carl Curran told the BBC that he and his family's planned flight to the UK from Sydney via Singapore on Tuesday became "impossible for us", as Singapore has shut its doors to transit passengers.
Other transit hubs, such as Doha and Kuala Lumpur, are still allowing UK travellers but the prices of tickets can be prohibitive.
What's been the response?
On Monday, UK authorities called on all British people travelling abroad to return immediately.
Louis Verkaik, 19, told the BBC he had been travelling alone on a gap year and had managed to get one of the last flights from NZ to Australia.
He has found last-minute accommodation with family friends outside of Sydney but will need to quarantine for 14 days as per Australia's rules.
"I'm not getting any real support. Everyone passes me off to the high commission who have shut their lines," he told the BBC.
"I've sent an email stating that the British government should send over an emergency flight for people such as myself stuck. I don't have enough money to sustain myself for very long."
The UK High Commissioner in Australia, Vicki Treadell has said officials are speaking with airlines to find "workable solutions".
To #British travellers: we understand the urgency of the current travel situation. We’re speaking to airlines, working across our wider Asia Pacific network to secure transit options & in close touch with the Australian Govt on internal travel & transit issues.#coronavirus pic.twitter.com/rVkfwzBma1— VickiTreadell (@VickiTreadell) March 24, 2020