Video report by ITV News Political Correspondent Romilly Weeks
"Technical issues" mean the government's newly launched online portal - built for travellers to book a Covid quarantine hotel when arriving from a 'red list' country - will be offline overnight.
The website went live on Thursday afternoon but promptly crashed shortly afterwards.
UK nationals or residents returning to England from 33 “red list” countries will be required to spend 10 days in a government-designated hotel from Monday.
The online portal will remain down overnight due to a “minor technical issue”, a Department of Health spokesman said - it is understood officials are expecting the booking site to be back up and running by around 10am on Friday.
When it came back online, briefly, on Thursday ITV News tried to book a hotel room for February 15 - the day the quarantine plan comes into effect.
The portal gives users the option to book hotels near eight airports, yet rooms were only available in Edinburgh.
No rooms can be booked on February 15 near busy airports like Heathrow, Gatwick and Birmingham.
The government portal ITV News attempted to book a room with can be found at quarantinehotels.ctmportal.co.uk.
However, a separate portal - quarantinehotelbookings.ctmportal.co.uk - holds a contrasting message. The most recent update said 'we'll be back soon' - but did not give a time.
The message on the site said: “Sorry for the inconvenience but we’re performing some maintenance at the moment."
The spokesman said: “The website is currently undergoing work to correct a minor technical issue.”
He said the portal will be open “well before” the hotel quarantine scheme comes into effect on Monday.
Last week, ITV News learnt that passengers arriving to the UK from countries on a government travel ban list will have to quarantine in government approved accommodation, such as hotels, from February 15.
Foreign nationals from 33 countries where new variants have been identified - including South Africa, Portugal and South American nations - are banned from entering England.
Those in quarantine will be required to take a Covid-19 test on both Day and Day 8 of their stay.
After the system crashed, shadow home secretary Nick Thomas-Symonds said ministers must act urgently to get it back up and running.
“It is extremely worrying that even the limited hotel quarantine booking system is showing signs of failing from the outset,” he said.
“Over a year into this pandemic and 50 days on from the discovery of the South African strain, there are no excuses for yet more Government incompetence in the introduction of hotel quarantine.
“Ministers must act to fix this urgently.”
Rory Boland, Editor of Which? Travel, said the government must ensure there are enough hotel rooms available.
He said: “If mandatory hotel quarantine is to be effective, it is essential the government ensures there is enough provision of rooms to accommodate UK arrivals from red-list countries, to save anyone being left stranded abroad and significantly out of pocket for reasons beyond their control.”
Health Secretary Matt Hancock announced on Tuesday that arriving travellers put in quarantine hotels will be charged £1,750 for their stay.
The guidance states that it will cost £650 for a second adult or child aged over 12 to stay in the room, and a further £325 for a child aged between five and 12.
The costs – which the Department of Health said will be reviewed before the end of March and may change – cover transport to the hotel, food, accommodation, security, other essential services and testing.
People on income-related benefits have the option to apply for a deferred repayment plan when booking, which will require them to pay back the cost in 12 monthly instalments.
Passengers arriving into England face fines of up to £10,000 for failing to quarantine, and those who lie on their passenger locator forms face up to 10 years in jail.
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