Ranking Republican and Democratic members of the House Committee on Oversight and Government Reform told NFL Players Association Executive Director DeMaurice Smith they're determined to talk to players about HGH use in the sport, The Washington Post reported.
The union, which maintains HGH use isn't a problem among players, has been negotiating with the league for two years on the rules for a blood-testing program, which was agreed to in its 2011 collective bargaining agreement.
"While NFLPA management may not believe that HGH is a problem in the NFL, the words of your athletes suggest otherwise," Reps. Darrell Issa, R-Calif., and Elijah Cummings, D-Md., wrote to Smith in a letter released Monday.
"... Although you have requested previously that we communicate directly with the NFLPA on these matters, we now ask that you and your staff not interfere with our efforts to communicate directly with the players or their personal counsel," the letter stated.
The NFLPA is asking the NFL to perform a population study to determine what levels of HGH would constitute a positive test, further delaying an agreement, the Post said.