North Carolina is bracing for tropical storm-force winds and rain as Hurricane Maria moves north, according to the US National Hurricane Centre.

Maria has been downgraded to a Category 2 storm from Category 4, but is still capable of producing “some direct hits” along the US east coast.

“Since Maria is a large hurricane, the associated tropical storm-force winds could reach a portion of the North Carolina coast by midweek regardless of the exact forecast track,” the centre says.

The US territory of Puerto Rico was among the worst-hit areas when Maria crossed the Caribbean as a Category 4 storm last week.

Officials warn the island could take years to rebuild its infrastructure, including power grids.