ExxonMobil Corp.’s US marine affiliate, SeaRiver Maritime Inc., signed an agreement with Aker Philadelphia Shipyard for construction of two US-flagged Liberty Class crude oil tankers. The double-hull, 115,000-dwt vessels will be used to transport Alaska North Slope crude to the US West Coast.

SeaRiver expects construction to begin by mid-2012, with the 730,000-bbl tankers scheduled for delivery in 2014. The ships will replace two existing double-hull tankers.

The vessels will cost about $400 million together. Aker will build the ships in partnership with Samsung Heavy Industries.

The agreement follows a letter of intent signed for the vessels earlier this year (OGJ Online, July 26, 2011).