Mayor Wang Qishan acknowledged residents were frightened and that there had been some public panic. But he denied speculation that the Chinese capital would be sealed off, saying enough precautions were in place.
"I think the coming week will be of critical importance in monitoring the trend of development of this disease," Wang said at a news conference.
He called for calm and said "the panic and fear factor among the general public is a really big issue for us."
The Health Ministry reported nine new fatalities in Beijing and two elsewhere, which raised the capital's death toll to 75 and the total for the mainland to 159. The ministry said there were 101 new infections in Beijing, raising its total to 1,448.
"The situation in Beijing remains severe for SARS prevention and treatment. Infections have not yet been cut off. Numbers of confirmed and suspected SARS cases remain high," Wang said in a written statement.
"Due to a shortage of berths at designated hospitals, not all suspected SARS patients can be hospitalized there in a timely manner."
The city has designated 21 hospitals to handle SARS cases, Wang's statement said. It didn't say how the suspected cases that weren't hospitalized were being handled.
The rising number of infections has prompted increasingly urgent steps to stem the spread of the virus.
The Beijing government has closed public schools and ordered cinemas and other entertainment sites to close.
The city has "segregated" 8,924 people who might have been exposed to the virus, according to a city government statement issued overnight Tuesday.
A new 1,000-bed SARS hospital was built in eight days by 7,000 workers and was to open Wednesday.
Nationwide, the upcoming May Day vacation week has been cut short and the government has banned travel agencies from taking tourists out of their home provinces. Worries about the disease prompted thousands of people to flee Beijing last week.
Rumors that martial law might be declared or that Beijing might be closed spread last week after police roadblocks were set up to check people in vehicles for SARS symptoms and the city said it would seal off buildings or areas with infections.
Wang denied the reports, and said no cases had been reported in rural villages around the capital. He said every household there had been issued a thermometer and told to check family members daily for fever — a key SARS symptom.
SARS has killed at least 373 people worldwide, out of more than 5,400 infected.
In developments outside of mainland China:
The lifting of the warning could not have come soon enough, reports CBS News Correspondent Jim Axelrod: By one estimate, SARS could end up costing the Canadian economy $1.5 billion. In Toronto and the entire province of Ontario a good chunk of that loss will be in tourism.
Warnings still stand for Hong Kong, Beijing and two Chinese provinces.