Washington ? The White House’s director of postwar policy for Iraq, who was instrumental in helping to set up an interim government to lead that country until elections can be held, is stepping down.

Robert Blackwill, a former ambassador to India, has overseen Iraq strategy at the National Security Council since mid-2003. He decided “some time ago” to depart government service after the presidential election, a White House official, speaking on condition of anonymity, said Saturday.

Blackwill’s departure was first reported Saturday in The Washington Post. It was the second report in two days of a ranking official’s decision to leave the Bush administration’s national security establishment.

On Friday, the State Department confirmed the impending departure of J. Cofer Black, the department’s chief counterterrorism figure. Like Blackwill, the former CIA operations officer had told superiors he planned to leave after the elections, and department spokesman Adam Ereli said he would end his 30-year government career in a matter of weeks.

Blackwill’s absence will shorten the list of people reputed to be in the running to replace Condoleezza Rice as President Bush’s national security adviser. Rice has told associates she will not stay in the post in the second Bush term and has talked about returning to academic life in California. She was a former provost at Stanford University and was a political science professor when Bush hired her.

Blackwill, whose formal title is coordinator for strategic planning on the NSC, spent months slipping in and out of Baghdad to put a U.S. stamp on a caretaker government in Iraq. The career diplomat was on the short list to become ambassador to Iraq in the spring, but Bush instead chose John Negroponte, former ambassador to the United Nations.

Blackwill worked at the National Security Council in the first Bush presidency. After advising the current president during the 2000 campaign, he spent nearly two years as ambassador in New Delhi. He served at the State Department under Secretaries Henry Kissinger, Alexander Haig and George Shultz and has spent nearly 15 years teaching foreign and defense policy at Harvard University’s John F. Kennedy School of Government.