Carnival Corp plans to bring a handful of idle ships back into service this summer while the US government launches an investigation into its approach to the Covid-19 pandemic.

Carnival Cruise Line expects to pull up anchor on eight ships on 1 August to resume North American itineraries from Galveston, Texas, and Florida's Miami and Port Canaveral.

"We are committed to supporting all public health efforts to manage the Covid-19 situation," the Christine Duffy-led operator of 26 ships said in a statement.