LOS ANGELES (REUTERS, AFP) - California's governor on Thursday (March 19) issued a statewide "stay at home order" directing residents to leave their homes only when necessary during the coronavirus pandemic.

Governor Gavin Newsom said that modelling has shown that 56 per cent of California residents were expected to contract the Covid-19 disease over the next eight weeks, requiring nearly 20,000 more hospital beds than the state could currently provide.

Newsom earlier on Thursday asked President Donald Trump to send a US Navy hospital ship to the port of Los Angeles "immediately" as the state braces for the expected surge in the number of coronavirus cases.

He said Los Angeles, as the nation's second-largest city, would likely be "disproportionately impacted" by the pandemic in the coming weeks.

In a separate letter sent to US congressional leaders, the governor asked for additional federal funding for unemployment insurance and social safety net programs and aid to small businesses, schools and universities.

Los Angeles residents were also ordered to stay at home by the city's mayor Eric Garcetti on Thursday.

"I'm issuing a Safer at Home emergency order - ordering all residents of @LACity to stay inside their homes and immediately limit all nonessential movement," he tweeted. "We're taking this urgent action to limit the spread of Covid-19 and save lives."