The $1.01 trillion federal spending bill that congressional leaders unveiled Tuesday night includes $100 million to build a light-rail Purple Line in the Maryland suburbs,  Sen. Barbara Mikulski (D-Md.) said Wednesday.

If the money remains in the final approved bill, it would be the first significant federal aid for the 16-mile light-rail project that would connect Montgomery and Prince George’s counties.

The Maryland Transit Administration is seeking $900 million in highly competitive federal construction funding for the Purple Line, which is estimated to cost $2.45 billion to build. The Federal Transit Administration has recommended the project for a “full funding grant agreement,” but a final deal has not been reached.

The federal spending bill also includes $100 million to build a 14-mile Red Line in Baltimore, Mikulski said.

Maryland transit officials have said construction could begin on a Purple Line in 2015, but Gov.-elect Larry Hogan (R) has not said whether his administration will continue the project.