Morocco's government on Wednesday extended a medical state of emergency until next month in the face of a sharp rise in coronavirus cases.

"Today, the cabinet approved a project for a decree extending until October 10 the duration of the medical state of emergency to combat Covid-19," Prime Minister Saad-Eddine El Othmani tweeted.

Morocco's economic capital of Casablanca, with 3.3 million residents, has been under lockdown since Monday, including a night-time curfew and closure of schools.

Emergency measures were first put in place in March.

Casablanca, along with Marrakesh, had already been subject to a series of restrictions three weeks ago, including beach closures and shortened business hours.

All exits to major cities in the North African country have been closed, with travel only allowed with "exceptional authorisation" issued by local authorities.

"We risk being submerged by the virus," Health Minister Khalid Ait Taleb said Sunday.

"So drastic measures are in order, otherwise the situation risks spinning out of control in coming days."

With more than 1,000 confirmed cases a day since the start of August, Moroccan media have been critical of the handling of the health crisis.

The authorities blame the spread of Covid-19 in Morocco on people's failure to adhere to health protocols.

The country of 35 million inhabitants has recorded more than 1,400 deaths from coronavirus and over 75,721 confirmed cases.