— Virginia Gov. Robert F. McDonnell appointed lawyer James Dyke on Friday to serve on Metro’s board of directors as he seeks to exert some long-sought authority over the second-busiest subway system in the nation.

The move was met by criticism and confusion from local leaders in Northern Virginia who said they resent McDonnell’s administration trying to influence a regional issue they understand better.

Jeff McKay, an alternate member to the Metro board who serves as a supervisor on the Fairfax County Board, praised Dyke, who is well known in Washington-area business circles, but faulted McDonnell (R) for not informing them of the decision.

“This administration hasn’t had the decency to sit down with the board,’’ he said. “We were kept in the dark. This appointment raises more questions than answers.”

The change will force the Northern Virginia Transportation Commission, made up of of 19 local and state elected officials plus the state’s public transportation director, to relinquish one of its seats on the Metro board.

“Somebody would have to step off as a voting member because [the governor] clearly wants to appoint someone who would have a vote to WMATA,” said Mort Downey, a principal board member appointed by the federal government.

McDonnell’s decision fulfills a pledge to appoint a Northern Virginian of his own choosing to the 16-member Washington Metropolitan Area Transit Authority board. He has maintained for more than a year that Metro needs more input and oversight from state government.

Dyke will be hired by the state and paid $65 an hour. Representatives of Virginia localities receive a $50 stipend per meeting, but board pay varies widely among jurisdictions.

Thelma Drake, director of the Virginia Department of Rail and Public Transportation, said some Metro board members and the NVTC chairman were informed of McDonnell’s plans.

“This issue has been discussed and debated,’’ said Sean Connaughton, Virginia secretary of transportation. “They have openly opposed our efforts to be on the board. . . This obviously should come as no surprise.”

McDonnell had pushed for months for at least one seat on the board but had been thwarted by local officials in Northern Virginia, primarily Democrats, who opposed the effort.

In April, Virginia’s divided General Assembly unexpectedly voted for a budget amendment giving the governor a seat starting July 1 — continuing significant turnover on the Metro board.

Dyke, a partner at McGuire Woods, has worked for Democrats — former Virginia governor L. Douglas Wilder and former vice president Walter Mondale — and served as chairman of the University of the District of Columbia’s board.

“Mr. Dyke is the best candidate to represent the commonwealth’s vision for transit choices in the Northern Virginia region as he has first-hand experience with the transit system in the region; a history of being non-political, serving Virginia under both Democrat and Republican governors; and a clear interest in addressing problems and finding solutions,” McDonnell said in a statement.

Dyke was was chairman of the Greater Washington Board of Trade last November when it called for dramatic changes to Metro.

The joint task force of the Greater Washington Board of Trade and Metropolitan Washington Council of Governments recommended that Virginia, Maryland and the District change the agreement that governs Metro to increase the number of principal members from each jurisdiction from two to three, with one member appointed by the chief executive of each jurisdiction.

Each jurisdiction, plus the federal government, currently appoints two principal and two alternate directors.

Dyke, who lives in Reston, said he rides Metro regularly to the District and Maryland to attend meetings, work and Nationals games. He said he looks forward to helping provide “a safe, efficient and robust network of transportation choices.”

Drake will become an alternate to the NVTC board. Dyke will be sworn in as a member of the NVTC Oct. 6. NVTC officials said Dyke must be elected to the WMATA board by the NVTC, but Connaughton said the law states he should be an automatic member.

Some Metro board members said they worry that critical funding for the transit authority could become tied up if the governor threatens to withhold funding for the transit agency as he has done in the past.

Last summer, McDonnell threatened to withhold Virginia’s contribution to a $3 billion federal funding plan for Metro’s capital needs unless the state received two of Northern Virginia’s four seats on the agency’s board.

The federal government agreed to give Metro $1.5 billion for capital needs over 10 years but required that Virginia, Maryland and the District match the money. Virginia eventually paid its annual contribution.

This year Metro’s board has undergone significant turnover, with more than half of the 16-member board being replaced as Metro tries to move beyond the shadow of recent financial and safety troubles.