The prime minister of Sweden was forced to defend his Covid-19 strategy after opposition parties mounted a scathing attack on his government amid signs its handling of the pandemic has been fatally flawed.

With one of the world’s highest Covid mortality rates and Sweden’s chief epidemiologist admitting mistakes, Prime Minister Stefan Lofven was the target of a series of rebukes during a debate among party leaders broadcast on Sunday night.

Ulf Kristersson, the leader of the main opposition party known as the Moderates, said “there have been obvious, fundamental failures” in Sweden’s response to the pandemic.

Until now, lawmakers in Sweden had observed a tacit political truce when discussing the country’s Covid strategy. But that all changed last week, when state epidemiologist Anders Tegnell acknowledged that some of his decisions may have been misguided.

Since the virus hit, Tegnell has advised the government to leave most of society open, on an assumption that doing so would be more sustainable in the long run. Even more controversially, he has argued against using face masks, pointing to what he’s characterized as a lack of evidence that such coverings are effective.

But at 4,694 deaths as of Monday, Sweden’s Covid mortality rate is now among the highest per capita in the world, and many times higher than in the other Scandinavian countries.

Lofven acknowledged that there was room for improvement, but said there’s no reason to abandon Sweden’s approach. “The strategy is the right one,” he said during the debate on Sunday.

Tegnell has also insisted his strategy remains appropriate. At a press briefing on Monday, he said a growing number of Swedes now have mild cases of the virus. That means Sweden will see “more cases for a period, but in the long term we will have better control of the pandemic,” he said, according to Dagens Industri.

Pressure is mounting on Lofven as Sweden’s response to the virus puts it on a dramatically different path from countries that adopted much tougher lockdowns. Swedes suddenly find themselves facing travel restrictions in the European Union due to the high infection rate in their country.

A poll last week showed that Swedes’ confidence in their government’s handling of the pandemic plunged by almost 20 percentage points since April, to less than half the population. The figures suggest that political gains Lofven had made between November and May are unlikely to stick.

Lofven’s opponents are now seizing the moment to insist on change. On Sunday, the leader of the populist Sweden Democrats party demanded that Tegnell be fired.

Ebba Busch, leader of the opposition Christian Democrat party, criticized Lofven for a lack of leadership.

“The Swedish government has deliberately allowed a large spread of the disease,” Busch said. “In a difficult crisis, we will always be leaderless as long as this government is in power.”

--With assistance from Rafaela Lindeberg.

This article was provided by Bloomberg News.