The U.S. government issued its most severe warnings against travel to Britain this week as coronavirus cases and deaths there soared to the highest levels in months and authorities in England scrapped nearly all remaining restrictions in a bid to restart the economy.

The State Department and the Centers for Disease Control and Prevention on Monday urged all Americans to avoid visiting the country. “Even fully vaccinated travelers may be at risk for getting and spreading COVID-19 variants,” the CDC said in an updated travel notice.

In its highest-level advisory Monday, the State Department delivered an even sterner warning. “Do not travel to the United Kingdom due to COVID-19,” the advisory said.

Here are some significant developments:

  • Canada said it will begin to ease pandemic restrictions at the U.S.-Canada border beginning Aug. 9, allowing U.S. citizens and permanent residents who are fully vaccinated to enter for nonessential travel without quarantining.
  • Global stock markets swooned Monday, with the Dow tumbling more than 700 points. It was its worst one-day decline of 2021, as investors grow increasingly anxious about a delta variant-led resurgence in coronavirus cases and its potential to derail the economic recovery.
  • The coronavirus pandemic may have caused more than 4 million excess deaths in India, according to an estimate from the Washington-based Center for Global Development. India’s official covid-19 death toll stands at 414,000, a number experts believe is a vast undercount.
  • Russia’s total number of confirmed coronavirus cases topped 6 million Tuesday, the state-owned Tass news agency reported. Russia is suffering a spike in new infections and deaths as vaccinations lag behind.
  • A close confidant of deposed Myanmar leader Aung San Suu Kyi died in prison Tuesday after contracting covid-19, Agence France-Presse reported, quoting the country’s military authorities. The 78-year-old Nyan Win was a senior member of Suu Kyi’s National League for Democracy.
  • Muslims around the world Tuesday were observing a second Eid al-Adha, or Feast of the Sacrifice, in the shadow of the coronavirus pandemic. The celebration is normally marked by large gatherings and communal prayers — but authorities in some countries have restricted travel or appealed to worshipers to stay home to avoid spreading the virus.

The new U.S. travel warnings are not binding, but they were issued as Britain struggles to contain the fallout from a surge in new infections caused by the delta variant, first identified in India.

Even as new cases climbed in recent weeks, the British government forged ahead with plans to abandon most virus curbs in England on “Freedom Day” on July 19.

But the government said later Monday, just hours after videos showed revelers crammed into bars and entertainment spots as the clock struck midnight, that it would instate new rules to require people to provide proof of vaccination to enter nightclubs and other crowded venues.

The restrictions would take effect by the end of September, Prime Minister Boris Johnson said at a news conference, after residents over age 18 are offered the chance to be vaccinated.

“I don’t want to have to close nightclubs again,” Johnson said, according to BBC News. “But it does mean nightclubs need to do the socially responsible thing.”

Britain is reporting a seven-day average of roughly 45,000 daily new cases, according to Our World in Data, which tracks publicly available figures. Some of the country’s top leadership — including Johnson — are in quarantine after Health Secretary Sajid Javid tested positive for the virus during the weekend.

Johnson last week described the U.K. as undergoing an “exit wave” — an inevitable, conclusory rise in infections and deaths. At a July 6 press briefing, Johnson said that if restrictions couldn’t be opened up in the next few weeks, “we must ask ourselves, when will we be able to return to normal?”

On Monday, Johnson said in a briefing that the logic of reopening remains the same. “There comes a point, after so many have been vaccinated, when further restrictions no longer prevent hospitalizations and deaths — but simply delay the inevitable,” he said.

Still, he said, “the pandemic is far from over.”

More than half of the population has received two doses of a coronavirus vaccine, a level of immunization that officials say has helped prevent hospitalizations and deaths.

According to the government’s latest figures, hospitalizations have risen nearly 40 percent over the past week. But on Monday, Patrick Vallance, Britain’s chief scientific adviser, said 60 percent of hospitalizations from COVID are currently from unvaccinated people.

Deaths also climbed 60 percent week-on-week, with 22 confirmed Monday. On Tuesday, the fatality count spiked: The U.K. recorded 96 deaths in a 24-hour period — the highest death count since March 24, the tail end of a months-long surge.

When Britain was reporting similar daily case numbers during its devastating peak in January, more than 1,000 covid-related deaths were recorded each day.

More than half a million people were “pinged” by the U.K. government’s contact-tracing app between July 1 and 7, alerting users that they had possibly been exposed to the virus and should self-isolate for up to 10 days.

On Tuesday, Dominic Cummings, the prime minister’s former chief adviser, released to the BBC messages allegedly sent from Johnson to aides in mid-October. Johnson was hesitant to impose covid restrictions because those dying were “essentially all over 80,” Cummings told the BBC.

Johnson reportedly sent a message saying that the median age for covid fatalities was in the 80s — “above life expectancy,” he appeared to write. “So get Covid and Live longer.”

“And I no longer buy all this NHS overwhelmed stuff. Folks I think we may need to recalibrate,” he reportedly went on to write, in a message shared with the BCC.

Sammy Westfall contributed to this report.