LONDON: Britain on Monday will unveil plans to restart international travel as it cautiously exits a coronavirus lockdown, but India was forced to further tighten curbs to fight a huge spike in infections.

Even as vaccinations gather pace, the coronavirus is spreading rapidly in many parts of the world, forcing a return of lockdowns from Canada and Peru to Bangladesh and Italy.

But after inoculating more than 31 million people with their first dose, Britain is set to ease travel restrictions that include a ban on international trips except for a handful of permitted reasons.

"We are doing everything we can to enable the reopening of our country... as safely as possible," Prime Minister Boris Johnson said.

Britain has set a tentative date of May 17 for the resumption, with destinations ranked green, amber or red based on the virus threat.

People heading to low-risk green countries will simply take a virus test before and after they travel, but those going to amber or red destinations will have to self-isolate or quarantine afterwards.

But the government has said it is too early to say which countries will be tagged green.

British authorities are also planning trial runs of a virus certification system that will allow people to attend events such as football matches, and also roll out two free rapid tests for all England residents from Thursday.

This progress is in sharp contrast to the crisis in Europe, where many nations have been forced to reimpose deeply unpopular restrictions because of worrying surges while lagging behind Britain in vaccinations.

Italy and France imposed curbs before the Easter weekend, and new coronavirus restrictions were set to come into force in Ukraine's capital Kiev.

But in Greece, where the number of coronavirus infections and deaths remains high, authorities relaxed a nationwide lockdown on Monday, opening most retail shops.

There was alarm in India on Monday as it reported more than 100,000 new daily infections for the first time since the pandemic began, and its worst-hit state Maharashtra tightened an evening curfew from Sunday.

Prime Minister Narendra Modi's government is anxious to avoid imposing a new national lockdown after a shutdown in March 2020 caused widespread human and economic misery.

Bollywood superstar Akshay Kumar became the latest Indian celebrity to test positive, and said Monday that he was in home quarantine as a precaution.

Surjit Singh, an auto-rickshaw driver in the capital Delhi, blamed the situation on carelessness.

"The fear of Covid-19 has gone away. Most people don't wear masks properly, including many of my passengers," the 68-year-old told AFP.

Neighbouring Bangladesh also began a seven-day lockdown on Monday to fight a sharp rise in cases, with all domestic travel including flights suspended. Malls and shops were also closed.

Thousands fled the capital Dhaka on Sunday, while many were seen buying groceries in bulk ahead of the lockdown.

"We won't be able to support the family if this lockdown prolongs," said street vendor Murad Hasan.

"It is driving me crazy. What should we do?"

Along with economically punishing measures such as lockdowns, countries are also trying to ramp up vaccinations, seeking scarce supplies to try to end a pandemic that has claimed more than 2.8 million lives worldwide.

In his Easter Sunday address, Pope Francis called vaccines an "essential tool" in ending the pandemic and urged their swift rollout to the world's poorest countries.

But the persistent threat of the coronavirus was illustrated in Chile, where despite a high number of vaccinations, infections have skyrocketed and forced the country to shut its borders from Monday.

Travellers flocked to the airport in the capital Santiago on Sunday before the closure.

And despite the inconvenience, Ismael Bustos, who was travelling to Mexico, said it was "one hundred percent necessary".

"I think we should have been locked up a long time ago."