BERLIN — Several countries moved ahead with plans for the gradual reopening of their economies this week, signaling cautious optimism among their governments that measures to combat the novel coronavirus are working.

Germany and South Korea — role models in handling the outbreak in their regions — are slowly reversing some of the restrictions put in place weeks ago, embarking on a careful and long path back to normality that could serve as a template for other nations.

New Zealand Prime Minister Jacinda Ardern, however, extended a lockdown Monday but did so amid mounting hopes that her country can eliminate the coronavirus by tracing transmissions and preventing new infections.

Her move underscores the uncertainty over the best path forward as countries emerge from lockdown. In Germany, some scientists have argued that the country should ramp up restrictions until new infections reach a rate that makes tracking and contact tracing more easy, a strategy they say will allow for a greater degree of freedom in the long run.

But political pressure has been mounting for a return to normality, with some German states pushing for greater freedoms as shops under 8,600 square feet began to open Monday. Chancellor Angela Merkel urged vigilance.

“It would be a terrible shame if we were to go straight into a relapse,” she said at a news conference. “We must not become careless; we must not lull ourselves into a false sense of security.”

Merkel stressed, “We have not reached the peak.”

The number of coronavirus deaths in Europe surpassed 100,000 this weekend. Many European nations, including Britain and France, remain under tight lockdowns and are expected to stay under heavy restrictions for weeks.

But leaders must weigh the economic impact. Unemployment could almost double, as tens of millions of jobs on the continent are at risk, according to the McKinsey consulting firm.

With a relatively low debt burden after years of economic growth, Germany is better positioned to endure a prolonged lockdown compared with many other European Union countries. But a relatively low coronavirus death toll has encouraged German officials to agree to a cautious easing of restrictions.

Many nonessential businesses reopened Monday, including car dealers, bookstores, zoos and electronics retailers. Restaurants, bars and most larger stores will remain closed.

Over 4,700 people have died of covid-19, the disease the virus causes, in Germany. By comparison, France has only a slightly higher number of confirmed infections but more than four times the number of deaths — a difference that health analysts have partially explained by pointing to more extensive testing and other mitigation efforts introduced in Germany early on.

But Merkel said any relapse could mean a snapback in restrictions. In a meeting with her party leaders earlier on Monday, she raised concerns about a “discussion orgy” on opening the country, German media reported.

Explaining her comments at the news conference, she said she feared discussions were moving at a pace that assumed a level of security that is “not there.”

State leaders and the federal government last week agreed to keep social distancing measures in place until May 3. To lift them, Germany must be able to better track infection chains, she said, with a team of at least five contact tracers for every 20,000 people.

“We need to uncover every infection chain,” she said. “To be honest, we can’t do that right now.”

Last week, Spain allowed some workers to resume operations, even though it extended the restrictions that have kept people locked inside their homes for weeks. And while Austria reopened many shops, it tightened rules on the use of masks in public settings.

On Monday, Denmark and the Czech Republic followed suit and similarly reopened some smaller stores. Norway is allowing children back into kindergartens, and Poland has made parks and forests accessible again.

In South Korea, the government went further, opting to lift closure advisories related to high-risk venues such as churches, bars and sporting facilities. South Korea’s death toll from the coronavirus stood at 236 Monday evening, making its fatality rate one of the lowest among countries with major outbreaks. The number of new infections in South Korea was below 100 for the 19th day in a row on Monday.

Prime Minister Chung Sye-kyun announced Sunday that while the social distancing policy will be extended for 16 more days, guidelines will be eased.

“Now that online classes and work from home have become a new normal, we have the room to consider balancing infection control and economic activities,” Chung said at a governmental meeting Monday. Schools remain shut as classes have gone online, while employees at many businesses still work remotely.

Although daily infection numbers have dwindled, risks from small outbreaks remain, Health Minister Park Neung-hoo said at a briefing Sunday, citing major public activities recently such as an election Wednesday.

The same fear of new outbreaks compelled the government of New Zealand on Monday to extend its strict lockdown — which was to end at 11:59 p.m. Wednesday — for five days, despite good results in its drive to contain the coronavirus.

New Zealand followed a “go hard, go early” strategy that involved shutting borders and locking down the country while the number of cases remained low. As a result, its transmission rate — the number of new infections that each person with the virus causes — is 0.48, compared with an international average of 2.5, Ardern said.

The Health Ministry reported Monday that nine new cases have been found, taking the nationwide total to 1,440. More than two-thirds of those infected have recovered. Twelve people have died, all in their 70s or older.

Starting April 28, workplaces in New Zealand that can maintain distance between workers and customers will be allowed to reopen. For most people, this will mean they have to continue to work and study at home and limit outside contacts.

Ardern said Monday that she does not want to undo the efforts of “our team of 5 million” people to break the chain of transmission and risk having to “yo-yo” between levels of restrictions.

“I couldn’t feel prouder of the start we have made together,” she said in a televised news conference. “But I also feel a huge responsibility to ensure that we do not lose any of the gains we have made, either,” she added, underscoring the difficult choices that governments worldwide face.

Anna Fifield in Havelock North, New Zealand, Min Joo Kim in Seoul and William Glucroft in Berlin contributed to this report.