VT Halter Marine has secured a newbuilding contract worth $745.9m to build the first in a series of heavy polar icebreakers for the US Coast Guard (USCG).

The Pascagoula, Mississippi-based shipyard could see the contract’s value expanded to $1.9bn if options for two more vessels are exercised.

Construction work on the first vessel is expected to start in 2021, with delivery expected in 2024 with work extending to 2027 if the second and third vessels are built.