The Philippines has recorded the country's first locally acquired cases of the Delta variant, prompting authorities to reimpose stricter coronavirus measures in some areas as health experts sought bans on social gatherings, reports Reuters.

The Southeast Asian country is battling one of the worst Covid-19 outbreaks in Asia, but infection numbers have been declining since peaking in March and April, allowing for a gradual relaxation of restrictions.

Sixteen people had been found with the Delta variant, including five who had returned from the United Arab Emirates, Qatar and Britain, between April and June, health undersecretary Maria Rosario Vergeire told a news conference.

The other 11 were locally acquired cases, including a cluster of five people in the southern city of Cagayan de Oro. One patient had died after being hospitalised in Manila on June 28.

"The spread of COVID-19 globally, while being controlled by vaccination, is still being driven by these variants of concern," said Vergeire, as authorities announced a tightening of restrictions in Cagayan de Oro and Misamis Oriental province.