The government's "pathetic" policy on border control is responsible for the expected delay to lifting the last lockdown regulations, Keir Starmer has said.
Speaking on Monday ahead of Boris Johnson's announcement the Labour leader said the expected four-week extension to regulations was "the net result" of the prime minister's "pathetic approach".
Addressing a radio phone-in Sir Keir lambasted the government for being slow to introduce hotel quarantine, allowing people travelling from high-risk and low-risk countries to mix at airports, and being slow to put India on the red list.
"Here we are, June 21 was supposed to be Freedom Day, and why are we not going to hit it? And it looks like we're not: Answer, because of the government's pathetic borders policy, absolutely pathetic," he told LBC radio.
"They didn't introduce hotel quarantine until I think February of this year, and then only 1 per cent [of travellers].
"Then we went through this ridiculous 'red, amber, green' [traffic light system] ... nobody knows where they are on that.
"And then the inexplicable delay from the 9th I think to the 23rd of April in putting India on to the red list, with lots of people coming in, and then on top of all of that and mixing at Heathrow Airport of people on red lists and green lists. Pathetic.
"That is why we are here and the Delta variant has got in because of the government's pathetic control of the borders."
The government had hoped to end all legal restrictions by 21 June but rising cases of the more transmissible Delta variant have made ministers think twice, with an announcement expected by Mr Johnson at 6pm.
Polls suggest relatively strong support for a delay to the final lifting of regulations which include the reopening of some final hospitality venues like nightclubs.
Health minister Edward Argar told the BBC on Monday morning that delaying the lifting of restrictions by a month would allow allow another 10 million second coronavirus vaccine doses to be put into people's arms.
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