Dutch Prime Minister Mark Rutte admitted Monday his government made a mistake by easing a raft of measures to combat Covid-19, apologising as daily infection rates rocketed to peak levels.

Rutte and Health Minister Hugo de Jonge on Friday reimposed a number of restrictions including closing nightclubs as the highly-infectious Delta variant took hold, particularly among young people.

"A judgement error was made. What we thought we could allow, we could actually not," Rutte said in The Hague.

"We are upset about it and we apologise," he told reporters.

More than 9,300 people tested positive on Sunday as opposed to 500 just two weeks ago, with the country reporting its highest daily numbers since December last year.

On Monday, 8,500 new infections were registered.

"The recent increase in numbers is faster than foreseen," the Dutch Outbreak Management Team (OMT) said in a letter to parliament last week.

"We're seeing a recent exponential increase in the number of infections specifically among 18-25 year-olds," the OMT said, adding infections happened mainly at nightclubs and within the hospitality sector.

However, it added: "Outside this age group there is no obvious increase."

Hospital admissions have also not risen significantly.

At a press conference on Friday, de Jonge said that some 80 percent of Dutch citizens have been vaccinated with at least one jab.

But virologists fear that young people with Covid could spread it to other age groups who have not yet been vaccinated.

The OMT warned that hospital admissions and "the burden of care" would likely go up again.

The Dutch decision came under fire including from the health minister of neighbouring Belgium.

"We've learned from the Dutch experience that it is best not to jump the gun," Frank Vandenbroucke told the VTM commercial television station.

Meanwhile the Dutch Event Organisers' Federation said it was "sad and furious" about the government's decision to reimpose measures to curb the virus.

"This feels like the death blow to an industry which was the only one working with the government to find a solution," it said, referring to a test-for-admission experiment which allowed people to attend events without having to keep 1.5 metres apart.