WASHINGTON (AP) — The head of the U.S. Agency for International Development is stepping down after two-and-a-half years of running America’s main foreign humanitarian aid programs.

Former Republican congressman Mark Green announced his resignation to return to the private sector on Monday, saying he was proud of the work the agency had done.

Green, one of President Donald Trump's few nominees for senior positions to win overwhelming bipartisan support in the Senate, said his last day on the job would be April 10.

Green oversaw an agency that, like the State Department under which it technically operates, faced perennial budget-slashing proposals from the Trump administration.

Although Green ran the agency with a philosophy of eliminating the need for foreign aid, he also championed disaster and emergency medical relief efforts in developing countries, particularly combating the Ebola virus in Africa. He was a Republican congressman representing Wisconsin from 1999 to 2007.

“The purpose of foreign assistance is to end the need for its existence,” Green wrote in a farewell letter to staffers. “The work of USAID every day provides a powerful return on investment to the American taxpayers for our national security, our economic growth — this generosity is simply in our DNA.”

Secretary of State Mike Pompeo thanked Green for his service and dedication. “He is leaving his Agency in a strong and vital position to address the new challenges this century will bring to us,” Pompeo said in a statement.

Reflecting the bipartisan support that Green held on Capitol Hill, the top Democrat on the Senate Foreign Relations Committee, New Jersey Sen. Robert Menendez, also lamented his resignation. “Administrator Green never shied away from speaking truth to power, and he leaves a legacy of working honestly and transparently across the Executive and Legislative Branches to do what is in our collective interest," Menendez said. “He will be sorely missed."