Boris Johnson has said the government has “increasing confidence” that Covid vaccines are effective against “all variants” of the illness. 

Speaking during PMQs on Wednesday, the prime minister said the spread of the Indian variant was “one of the issues” that could stop the June 21 unlocking date being hit.

 “We’ve looked at the data again this morning and I can tell the House we have increasing confidence that vaccines are effective against all variants, including the Indian variant,” Johnson told MPs.

Labour leader Keir Starmer said the government had been wrong to “weaken travel restrictions” given the threat from new variants.

It comes as the government faces calls for clarity over where foreign holidays are allowed after ministers appeared to contradict themselves.

There are green, amber and red lists for international travel. The ratings determine the quarantine and coronavirus testing requirements people face when returning home.

Johnson has said countries on the amber list are “not somewhere where you should be going on holiday”.

But environment secretary George Eustice said people could go to amber-listed countries as long as they observed quarantine rules on their return.

Welsh secretary Simon Hart told Times Radio “some people might think a holiday is essential” and therefore would be allowed.

And despite the presence of a green list comprising 12 countries and territories, health minister Lord Bethell said all foreign travel was “dangerous” and urged Britons to holiday at home this summer.