Angela Merkel has said the coronavirus pandemic is “still at the beginning” and parts of Germany may be rushing their exit from lockdown, as divided EU leaders clashed at a video summit over a desperately needed Europe-wide recovery fund.

Worried that Germans were relaxing physical distancing efforts amid the reopening of smaller shops this week, the chancellor said some of Germany’s 16 states were moving too fast and the country remained “on the thinnest ice” despite its early achievements.

Germany has the fifth highest number of confirmed coronavirus cases in the world, but has managed to keep its death toll down to just over 5,000, a far lower tally than in many other countries, mainly through early and extensive testing.

“It is precisely because the figures give rise to hope that I feel obliged to say that this interim result is fragile,” Merkel told parliament. “We are still far from out of the woods. We are not in the final phase of the pandemic, but still at the beginning.”

Play Video 1:38 Merkel sets out clear explanation of how coronavirus transmission works – video

Christian Drosten, the director of the Institute for Virology at Berlin’s Charité hospital, said reopening shopping malls and larger stores could trigger a second wave in May and June, and the country risked “gambling away” its early advantage. Schools in Germany are due to reopen from 4 May and Merkel and state leaders are due to meet again on 30 April to review how to proceed after that.

In France, Emmanuel Macron said on Thursday that a detailed plan to exit lockdown would be unveiled early next week. Pupils will return to French schools from 11 May, and the finance minister, Bruno Le Maire, said he hoped retailers other than restaurants, bars and cafes could reopen from the same date.

“We want all retail outlets to be able to open in the same way, out of fairness,” said Le Maire. Bars and restaurants were unlikely to reopen before mid-June “because they are places of mixing”, he added.

Retailers would need to limit the number of people in their shops at one time, Le Maire said, and the hardest-hit regions, such as eastern France and greater Paris, may have to wait longer for shops to reopen. Older people’s movements may also be restricted.

The public health authority chief, Jérome Salomon, said avoiding a second wave of infections remained the priority.

“France’s goal is not to create collective immunity by creating a second and then a third wave,” he told a parliamentary hearing. “That seems too dangerous to us. The goal is to prevent the circulation of the virus, and to create favourable conditions allowing us to gain time before the arrival of effective drugs or vaccines.”

Companies have been told they should encourage employees to continue working from home if they can to limit public transport use, and the government aims to raise its testing programme to about 500,000 tests a week. France has the world’s fourth highest death toll at more than 20,000.

In Italy the northern region of Lombardy, at the centre of Europe’s worst outbreak, began an antibody testing programme as it prepared to start opening up its economy. Blood tests to establish whether someone has had – rather than currently has – the disease will be carried out in 14 of the worst-hit areas before being extended to the whole region next week.

Meanwhile, Sweden’s public health agency revised earlier statements about when the capital Stockholm was believed to have passed the peak of infections. A report by the agency published earlier this week, based on statistical modelling, said the capital region passed the peak of simultaneous infections on 15 April, with 86,000 people believed to be have been infected. But on Thursday it revised the date to 8 April, with 70,500 believed to have been infected.

As EU leaders haggled over a rescue package that has reignited a bitter north-south divide between member states, Merkel also said Germany was ready to make “significantly higher” EU budget contributions to help the bloc cope with the fallout from the pandemic.

She added, however, that calls from some EU countries for common debt with common liabilities were not the way to go. “That would be a very difficult process, cost time and wouldn’t even help anyone in the current situation, since we need rapid-fire instruments to tackle the crisis,” she said.

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