MEXICO CITY – President Andres Manuel Lopez Obrador pledged Wednesday to begin reopening Mexico’s economy next week – under pressure at home and from U.S. officials – even as the country saw its largest one-day jump in coronavirus cases, hospitals are reeling, and testing remains inadequate.

Economy Secretary Graciela Marquez said the move would be “gradual, orderly and cautious,“ and that by May 18, industries like construction, mining, and car and truck manufacturing would be allowed to resume. But the governor of a state that is home to major auto plants warned that lifting restrictions now could lead to the pandemic getting “out of control.”

The country’s lockdown – which began in March – will remain in place, but work in the industries Marquez cited will be allowed to begin again because Mexico’s top advisory body on the pandemic, the General Health Council, said Tuesday it had decided to classify them as “essential activities.”

Mexico has been under pressure from U.S. officials to reopen auto assembly plants, in particular, because without them, integrated supply chains would make it hard for plants in the U.S. and Canada to reopen. At home, the National Alliance of Small Business Owners has also complained about lockdown measures, often imposed, quasi-legally, at the local level.

But others in Mexico fear a reopening – saying the measures were too long in coming and haven’t been in place for long enough. The announcement came as hospitals from Mexico City to its northern border with the U.S. were nearing overload, and many manufacturing workers in border cities like Ciudad Juarez had only recently been sent home in the wake of protests demanding a shutdown.

Mexican health officials on Tuesday reported the country’s largest single-day jump in COVID-19 case numbers, with 1,997 new cases and 353 deaths, bringing the total to over 38,000 confirmed cases and almost 4,000 deaths.

Officials have acknowledged the actual number of infections is many times that. Mexico has done relatively little testing, with about 120,000 tests reported so far in a country of almost 130 million. With only about 0.6 people per 1,000 inhabitants tested, Mexico has the lowest rate in the Organization for Economic Cooperation and Development.

That will make it hard to judge whether the reopening will risk an upsurge in cases – and to see one coming if it does. Marquez, the economy secretary, said that schools and businesses would be allowed to reopen in 269 townships that have no confirmed cases – or in about one-tenth of Mexico’s townships. They are largely in rural areas in north-central and southeastern Mexico.

Dr. Miguel Betancourt, president of the Mexican Society of Public Health, cautioned against putting too much stock in the safety of opening places with no recorded cases, given the low level of testing.

“Without a well-implemented system of monitoring or an adequate laboratory testing capacity in these areas, they don’t really know precisely what the situation is,“ he said. “Just because there aren’t any cases right now, doesn’t mean there won’t be later.”

Assistant Health Secretary Hugo Lopez-Gatell said Wednesday the Mexican government is evaluating more widespread testing, but that it probably wouldn’t start until July.

The auto and other manufacturing plants that the U.S. wants reopened – and that the Mexican government is pushing to restart – often depend on parts made at factories along the border known as maquiladoras. Ciudad Juarez is home to hundreds of such plants.

While many closed when the lockdown began, others were considered essential and still others tried to eke out a few more weeks of production. But as the virus spread like wildfire through factory floors, workers demanded to be sent home with full pay. There have been reports from workers, companies and labor activists of dozens of deaths among employees in such plants.

Susana Prieto, a labor lawyer who advises workers at maquiladoras, said the decision showed the government was yielding to pressure from multinationals.

“Is it safe?” Prieto asked with disbelief. “It is safe to say that the president of Mexico is a puppet of Mexican and foreign (businesses) that do not care about the lives of Mexican workers.”

For most people, the new coronavirus causes mild or moderate symptoms. For some, especially older adults and people with existing health problems, it can cause more severe illness and can lead to death.

U.S. officials have suggested the supply chain of the North American free trade zone could be permanently affected if Mexican factories didn’t resume production.

Christopher Landau, the U.S. ambassador to Mexico, launched a Twitter campaign last month, writing: “There are risks everywhere, but we don’t all stay at home for fear we are going to get in a car accident … The destruction of the economy is also a health threat.”

The pressure for reopening is building as well in Mexican states where the lockdown has caused huge job losses.

Carlos Joaquin Gonzalez, the governor of the Caribbean coast state of Quintana Roo – home to resorts like Cancun – said his state has lost 22% of its jobs after about 8 million people canceled trips to the area this year.

“Obviously, this requires us to think about reopening – as soon as possible,” Joaquin Gonzalez said.

Nationwide, Mexico has lost about 500,000 jobs due to the pandemic, and the auto industry appears eager to get back to work.

Volkswagen de Mexico is planning to reopen plants in Puebla and Guanajuato states.

But the governor of Puebla said that sending an estimated 37,000 auto industry employees back to work on May 18 “undoes all the (health safety) measures, it finishes off everything.”

“The rebound in contagion, and I say this as a matter of probability, could be very, very high, it could get out of control,” Gov. Miguel Barbosa said Wednesday.

General Motors said it hadn’t fixed a date for reopening its plant in Guanajuato, but some workers there reported getting notices to report for work on May 18. Ford said it was waiting for government approval to reopen.

Lopez Obrador said reopenings would be left largely up to individual states to decide how to proceed.