Philippine President Rodrigo Duterte announced plans Thursday for a sweeping lockdown of the capital's 12 million people, including a halt to domestic travel, in a bid to contain the deadly new coronavirus.

Though the nation has detected a fraction of the cases seen in hotspots such as China and Italy, officials hope to arrest the spread before it takes firm root in Manila's densely packed neighbourhoods.

During a nationally televised address, Duterte also announced a month of school closures, ban on mass gatherings and a prohibition on the entry of foreigners from places where the contagion is spreading.

"It's a lockdown," said the president, a popular leader locally but notorious internationally for his deadly drug crackdown.

"It's just a matter of protecting and defending you from COVID-19. That's about it."

It was not immediately clear when all the measures would take effect but Duterte said the prohibition on domestic sea, air and land traffic in and out of Manila would start Sunday.

The Philippines' tally of cases has risen from 24 to 52 since Monday and four of its five virus-related deaths were reported this week.

Cases globally now stand at more than 125,000 and 4,600 deaths, most of which have been in China.

Duterte's heavy-handed move comes after the World Health Organization urged countries to take action, saying the outbreak is a "controllable pandemic".

Philippine President Rodrigo Duterte took a coronavirus test Thursday
Philippine President Rodrigo Duterte took a coronavirus test Thursday AFP / Ted ALJIBE

The president himself underwent screening for the virus on Thursday as a precaution after coming into contact with government officials who were potentially exposed to the virus at recent public events.

The 74-year-old leader is in a vulnerable age group for the virus, which poses a greater risk to older people.

Critics expressed concern about how Duterte's lockdown would impact the potentially millions of workers who commute into Manila daily.

"This will only bring death and misery to millions of poor and struggling Filipinos who will be prevented from pursuing their livelihood," labour group Migrante International said in a statement.

Duterte also in the address touched on one of the most delicate and divisive features of his presidency -- his policy pivot towards long-time foe China.

The president has set aside the two nations' running standoff over Beijing's extensive claims to the disputed South China Sea to court trade and investment from the rising power.

"Maybe there will be a time, if things deteriorate, that I have to call on China to help," Duterte said.

"I hope it would not reach that point, but maybe we will need your help."