WASHINGTON (CNN) -- A bipartisan delegation headed by New Mexico Gov. Bill Richardson and former Secretary of Veterans Affairs Anthony Principi plans to visit North Korea this month to retrieve the remains of U.S. service members, a White House spokeswoman said Tuesday.

The Democratic People's Republic of Korea (DPRK) extended the invitation to "facilitate the return of the remains of missing servicemen," Deputy Press Secretary Dana Perino said in a written statement.

The White House also emphasized that it was the North Korean government that initiated the invite to Richardson because of his past experience in negotiating with the country. The White House asked that Principi be added to make the delegation bipartisan.

She said the trip is scheduled for April 8-11.

Richardson, a Democrat, is a 2008 presidential hopeful.

"The United States government has invested considerable energy in persuading the DPRK to adhere to the provisions of the armistice agreement that cover repatriation of remains," Perino said.

"This trip will reinforce progress already achieved in this area," she said. "A small number of U.S. officials will accompany the delegation to provide support and technical expertise."

The Korean War began in 1950 and ended three years later with an armistice.