A total of 16,509 patients have died in hospital after testing positive for coronavirus in the UK as of 5pm on Sunday, the Department of Health said, up by 449 from 16,060 the day before.
It is the second consecutive day that deaths have dramatically fallen, previously sitting at more than 800 a day for a period of several days.
In England, 429 people have died in recent days after testing positive for Covid-19, NHS England said. It brings the total number of fatalities there to 14,829.
The organisation announced 85 of the deaths occurred on Sunday, 210 on Saturday and 53 on Friday.
The figures also show 77 of the deaths took place between April 1 and April 16, and the remaining four deaths occurred in March, with the earliest new death taking place on March 21.
The delay in reporting can be attributed to delays in obtaining positive results, post-mortem outcomes, and for testing data to be validated.
A further nine people have died after testing positive for coronavirus in Wales, bringing the total number of deaths there to 584, health officials said on Monday afternoon.
Public Health Wales said a further 276 people had tested positive for Covid-19, bringing the total number of confirmed cases to 7,546.
Just over 900 tests were carried out on Sunday, with a total of 26,091 carried out in total across Wales.
Dr Giri Shankar, from Public Health Wales, said: "Based on the new case numbers there is emerging evidence suggesting a levelling-off in the number of new cases of Covid-19 in Wales, which may be an indication of the effectiveness of lockdown measures.
"However, it is still too early to tell for sure, and it is too soon to end the current social distancing rules.
"Public Health Wales continues to fully support the extension of lockdown measures, which is essential to avoid reversing the gains we have made in slowing the spread of this virus, protecting our NHS, and saving lives."
In Scotland, Nicola Sturgeon announced she will not rush to announce a lockdown exit strategy.
A further 12 people have died in the country, bringing the total number deaths to 915 patients.
Ms Sturgeon said 8,450 people have now tested positive for the virus in Scotland, up 263 from 8,187 the day before. She added 169 people are in intensive care with the virus or its symptoms, a fall of five from the previous day.
In total, 1,809 people are in Scottish hospitals with confirmed or suspected Covid-19.
The figures for Northern Ireland have yet to be released.
The coronavirus death toll in Ireland has risen to 687 after the deaths of a further 77 people were announced by the Irish Department of Health.
Number 10 remains hopeful of reaching 100,000 tests daily
Some 21,626 people in England, Wales and Scotland were tested for coronavirus in the 24 hours up to 9am on Sunday, Downing Street said.
Testing capacity dipped to 36,000 - from 38,000 last week - over the same 24-hour period, but the PM's official spokesman said this was due to commercial laboratories implementing new processes.
"That's not a permanent dip," the spokesman said.
More than 88,000 NHS and social care staff and their relatives have now been tested.
The spokesman added that the Government believes it is "on course" to meet the target of 100,000 tests a day by the end of the month.
First Minister Mark Drakeford has defended the decision to drop daily coronavirus testing targets in Wales.
The Welsh Government had previously set a target of 5,000 tests per day by the second or third week of April but it had dropped to fewer than 1,000 on Sunday.
Mr Drakeford said he had been advised the target was achievable when it was announced last month and was acting in "good faith" but had been let down by circumstances "outside our own control".