A two-week COVID-19 lockdown in China's economic capital of Shanghai has been eased on Tuesday as authorities allowed some residents to leave their homes after public outcry over strict measures and complaints that people were running out of food and other basic necessities.

The number of people who were allowed out in the city of 25 million wasn't immediately clear. The government said some markets and pharmacies also would reopen.

The abrupt closure of most businesses and orders to stay home left the public fuming about a lack of access to food and medicine. People who test positive for the virus have been forced into sprawling temporary quarantine facilities criticized by some as crowded and unsanitary.

Meanwhile, Washington set up a possible new clash with Beijing by announcing all "non-emergency U.S. government employees" would be withdrawn from its Shanghai Consulate while consular officers would stay.

"Our change in posture reflects our assessment that it is best for our employees and their families to be reduced in number and our operations to be scaled down as we deal with the changing circumstances on the ground," the announcement said.

The State Department also issued a series of advisories for Americans in Shanghai, including that they ensure they have a "sufficient supply of money, medication, food and other necessities for your family in the event of sudden restrictions or quarantine."

The Chinese government complained last week after the State Department said diplomats and their families could leave if they wanted.

The unusual severity of Shanghai’s shutdown starting March 28 appeared to be driven as much by politics as by public health concerns.

The struggle in China’s richest city is an embarrassment during a politically sensitive year when President Xi Jinping is expected to try to break with tradition and award himself a third five-year term as leader of the ruling Communist Party.

China’s case numbers are relatively low, but the ruling party is enforcing a "zero-tolerance" strategy that has suspended access to major cities to isolate every infected person. Some local officials were fired after being accused of failing to act aggressively enough.

The government reported 24,659 new cases through midnight Monday, including 23,387 with no symptoms. That included 23,346 in Shanghai, only 998 of whom had symptoms.

In Shanghai, more than 200,000 cases but no deaths have been reported in the latest wave of infections.

The government eased restrictions by announcing residents of Shanghai neighborhoods that have had no cases for at least two weeks would be allowed out of their homes starting Tuesday. It said they could go to any other area that also had no new cases during that time.

Shanghai has 7,565 such "prevention areas," according to city officials cited by state media. They gave no details of how many people were affected. People in 2,460 "control areas" with no new cases in the past week were allowed out but can’t leave their neighborhoods, the government said. Residents are barred from leaving their homes in "quarantine areas" that have had infections in the past week.

Shanghai has still not brought the outbreak under control and the number of new confirmed cases is expected to remain high over the next few days, a government health official said on Tuesday.

"The epidemic is in a rapid increase phase, with social transmission still not brought under effective control," said Lei Zhenglong of the National Health Commission at a briefing in Beijing.

"The forecast for the next few days is that the number of infected people will remain at a high level," he said.

The abrupt shutdown caught Shanghai households by surprise and prompted complaints they were left without access to food or medicine and were unable to look after elderly relatives who lived alone. The government distributed packages of vegetables and other food for a few days at least twice to some households. Others said they received nothing.

A video that circulated online Saturday showed what the caption said were people in the Songjiang district breaking into a supermarket and carrying away cartons of food. Another showed people thrusting their fists into the air in front of what appeared to be government employees wearing hooded white protective suits. A third showed what it said were apartment dwellers, barred from going outside, shouting appeals for help out their windows.

The Associated Press (AP) was unable to find the source of the videos or verify when and where they were shot. The supermarket video was labeled with an account number from China’s popular Sina Weibo social media service, but the video doesn’t appear on that account.

The ruling party requires Chinese social media operators to enforce censorship and remove videos and other postings about banned topics. Social media and online bulletin boards are filled with complaints about the Shanghai shutdown and appeals for food or medicine. It is unclear how many others might have been deleted.

Complaints about food shortages began after Shanghai closed segments of the city on March 28. Plans called for four-day closures of districts while residents were tested. That changed to an indefinite citywide shutdown after case numbers soared. Shoppers who got little warning stripped supermarket shelves.

City officials apologized publicly and promised to improve food supplies. Despite that, residents said online grocers often sold out early in the day or were unable to deliver. Online commerce companies said they added hundreds of employees to increase deliveries.

The State Department last week advised Americans against travel to China due to "arbitrary enforcement" of local laws and anti-virus restrictions. It cited a risk of "parents and children being separated."

The Chinese foreign ministry criticized that announcement as a "groundless accusation against China’s epidemic response."

On Tuesday, a State Department statement said the U.S. government decided "it is best for our employees and their families to be reduced in number" due to "changing circumstances on the ground."