The US has lodged a claim against Synergy Marine and Grace Ocean over costs that government lawyers tallied up to $103m after a container ship destroyed a Baltimore bridge.

The claim is the latest legal manoeuvre in litigation over a deadly casualty that saw the 9,962-teu Dali (built 2015) crash into the Francis Scott Key Bridge in March, killing six workers, cutting off traffic to a major port and launching a massive effort to remove debris from the shipping channel.