PORTLAND (AP) – The Navy has awarded nearly $12.6 million to Bath Iron Works for research and development linked to the DDG-1000 Zumwalt class destroyer program, U.S. Sen. Susan Collins announced Wednesday.

BIW has been working on detailed design work since last summer and the contract is expected to be awarded sometime this spring, Collins said.

The latest defense appropriation includes $2.6 billion for the first two destroyers of the class, with one each to be built at BIW and Northrop Grumman’s Ingalls Shipbuilding in Mississippi.