Construction was underway in November at the Dulles Airport Metro extension project (also known as the Silver Line) near Route and Spring Hill Rd in the Tysons Corner area. (Tracy A. Woodward/THE WASHINGTON POST)

LaHood called the closed-door meeting two weeks ago as Virginia politicians have grown concerned about a pro-union labor agreement and the board of the Metropolitan Washington Airports Authority, which oversees the building of the Silver Line, has shown no signs of changing the incentive they plan for bidders who use such deals.

But LaHood is likely to try to persuade the Airports Authority's board leaders to back off the 10 percent incentive for using a project labor agreement. In exchange, he will likely want Virginia politicians to firmly commit to giving the project $150 million, as they had said they would.

There is also concern that the newly elected, Republican majority of Loudoun County supervisors won’t vote to help pay their portion of the nearly $3 billion it costs to build the second phase of the rail line. Loudoun County has until July 4 to decide whether it is in -- or out -- on helping to pay its more than $200 million share.

The first phase of the rail line, which runs through Tysons Corner to Wiehle Avenue, is under construction and expected to be completed in August 2013.

The start of the bidding for the construction of the line’s second stage, which will run from Reston to Dulles Airport and Loudoun County, is already behind schedule.

LaHood is expected to meet with Virginia Gov. Bob McDonnell and Virginia Transportation Secretary Sean Connaughton in private on Wednesday, according to those close to the deal. He is then planning to meet with Connaughton, Metro officials, Loudoun and Fairfax county leaders and the chairman and chief executive of the Airports Authority.

Last fall, LaHood personally helped negotiate a financing deal for the second phase of the project.

Some watchdogs worry that if the parties don’t soon reach a deal on how to move the second phase forward, the rail line — if construction even gets started — could end at Dulles International Airport.

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