A Yemeni man, whose nephew and brother-in-law were killed in a US drone strike in 2012, has filed a lawsuit against U.S. President Barack Obama, former CIA director David Petraeus, former defense secretary Leon Panetta and several other unnamed persons, rights group Reprieve said on Monday.

Faisal bin Ali Jaber, who filed the 43-page lawsuit in a federal court in Washington, D.C., lost his brother-in-law Saleem, a 43-year-old anti-al Qaeda imam, and nephew Waleed, a 26-year-old police officer, in an August 2012 U.S. drone strike.

"The President has now admitted to killing innocent Americans and Italians with drones; why are the bereaved families of innocent Yemenis less entitled to the truth?" Faisal said while asking for a public apology from the U.S. government.

The lawsuit does not seek any monetary compensation from the U.S. Faisal, however, asked the government to declare the 2012 drone strike unlawful, reported the New York Times. 

"Since the awful day when I lost two of my loved ones, my family and I have been asking the U.S. government to admit their error and say sorry. Our pleas have been ignored. No one will say publicly that an American drone killed Salem and Waleed, even though we all know it. This is unjust," Faisal said. 

"If the U.S. was willing to pay off my family in secret cash, why can't they simply make a public acknowledgement that my relatives were wrongly killed?" he added in a press release issued by Reprieve.

The case is Salem bin ali Jaber et al v. United States et al, U.S. District Court District of Columbia, No. 1:15-cv-00840, according to Reuters. Reprieve U.S. and pro bono counsel at law firm McKool Smith are jointly representing him.

U.S. drone strikes in Yemen have killed up to 673 people, including around 100 civilians, from 2002 to 2015.