The National Rifle Association (NRA) said the policy that prohibits U.S. service members from carrying guns on military installations was "outrageous." Last week, a 24-year-old gunman opened fire at a military recruitment center, killing four U.S. Marines and a Navy sailor in Chattanooga, Tenn.

The NRA on Monday urged The White House to abolish its Pentagon directive that regulates who can carry firearms. The gun lobby also asked Congress to "pursue a legislative fix to ensure that our service men and women are allowed to defend themselves on U.S. soil," according to CNN.

"It's outrageous that members of our armed services have lost their lives because the government has forced them to be disarmed in the workplace," said Chris Cox, the leader of the NRA's legislative and political shop.

After the shooting rampage that took place last Thursday, several governors have taken measures to strengthen protection at National Guard facilities in their states, with some states ordering their National Guard unit to be armed, as HNGN previously reported.

Critics of the policy argued that had the service members been armed, the Chattanooga shooting could have been stopped, adding that other military base attacks, such as the 2013 Washington Navy Yard shooting that killed 12 people, or the shooting at Fort Hood that claimed 13 lives in 2009 could also have been prevented if the military gun law did not exist, The Hill reported.

Armed citizens have also started showing up at military recruiting centers across the country in order to protect recruiters following last week's shooting rampage, according to The Associated Press.