The NFL plans to begin taking blood samples from its players for human growth hormone within two weeks, Commissioner Roger Goodell said Friday after a Capitol Hill meeting with congressional leaders.

Leaders of the House committee on oversight and government reform said they emerged from the meeting with NFL officials and representatives of the players’ union with an understanding that the samples would be taken soon while the league and union work out the final details of the testing program over the next month so that it can be put fully into effect this season.

But the representatives of the NFL Players Association who participated in the approximately hour-long meeting stopped short of saying they had agreed to begin having blood drawn from players so soon. The union representatives reiterated that the players’ side will agree to begin having players blood-tested for HGH only when the union is satisfied that the test is reliable and safe.

The outcome of the meeting left it unclear whether significant headway had been made toward the sport implementing the testing . The league and union are to have a follow-up meeting with Rep. Darrell E. Issa (R-Calif.), the committee’s chairman, and Rep. Elijah Cummings (D-Md.), the ranking Democrat, within the next 30 days.

“I think the chairman has been very clear that testing should begin in the next two weeks or else he will expect to see us all in here again,” Goodell said following the meeting. “He expects to see us all in here within 30 days under any circumstance to give an update on how the process is taking place.”

Goodell said the league would begin drawing blood from players within two weeks because “that was the chairman’s instructions” and added that “everybody at the table agreed to that.”

But George Atallah, the union’s assistant executive director of external affairs, said the union’s view was that blood would be drawn from players “as soon as we have a fair and safe process in place.”

The union representatives, who included Baltimore Ravens cornerback Domonique Foxworth and former NFL player Ernie Conwell, did not provide a more specific timetable about when they expected testing to begin.

“We’re going to work on a fair process here to implement HGH testing in a fair and safe way,” Atallah said. “I think … the players are committed to that and we’ll do that as fast as possible.”

Cummings said he and Issa made it clear to the league and union representatives “that this ball has to move down the field immediately.”

“I think that with the schedule the chairman has laid out, that we’ve laid out together, it now gives them a road map to get to addressing this issue,” Cummings said.

As part of their new 10-year collective bargaining agreement, the league and union agreed that players would be subject to annual blood-testing and additional year-round random testing for HGH.

But negotiations on testing procedures have been at a standstill. Union officials have said they have not received the information they have sought about the safety and reliability of the test. NFL officials have said the test is reliable and safe.

The NFL would become the first professional sports league in the United States to blood-test its players for HGH with the consent of their union. Minor league baseball players are tested but they are not members of that sport’s players’ union.

Said Foxworth, a member of the union’s ruling executive committee: “It’s our responsibility to make sure that the test is accurate, that we check and we’ve done our own due diligence and we can look [players] in the eyes and say that this is a safe and fair process.”

HGH is on the NFL’s list of banned performance-enhancing substances but players currently are not tested for it.

A late-August meeting between the league, the union and representatives of the World Anti-Doping Agency failed to satisfy the union that its concerns had been addressed. The validity of the test was endorsed by scientists who wrote this month to the league and union.