Florida lawmakers have approved new congressional maps that could help Republicans maintain control of the thinly divided US House of Representatives in the midterm elections this year.

Florida Governor Ron DeSantis is expected to sign the measure into law, which could allow Republicans to gain as many as four House seats.

The move comes hours after the US Supreme Court limited the ability of lawmakers to take the racial make-up of a state into account when drawing voting maps.

Florida is the latest to join a national redistricting arms race that began after President Donald Trump urged conservative states to re-examine voting maps to help Republicans keep the congressional majority.

The midterm elections, which will decide who controls Congress, will take place in November.