Dennis Ross, a longtime diplomatic troubleshooter, has been appointed as a special adviser to Secretary of State Hillary Rodham Clinton, with responsibility for developing a strategy for engaging Iran.

The State Department notice of his appointment issued late last night did not mention Iran, and his official title is vague: adviser to the secretary of state for the Gulf and Southwest Asia. State Department officials said the title is a euphemism for Iran and issues affected by Iran's actions; it was kept obscure because Washington has not had diplomatic relations with Tehran since shortly after the Iranian revolution three decades ago.

President Obama has said he would like to engage with Iran and break through the years of antagonism between the two countries in an effort to stem Tehran's support of terrorism and pursuit of a nuclear weapon.

Ross "will provide to the Secretary and senior State Department officials strategic advice and perspective on the region" and "coordinate with senior officials in the development and formulation of new policy approaches," State Department spokesman Robert A. Wood said in a statement.

The statement noted that "this is a region in which America is fighting two wars and facing challenges of ongoing conflict, terror, proliferation, access to energy, economic development and strengthening democracy and the rule of law."

Ross, the latest in a series of high-level advisers and envoys appointed by Clinton, was the top Middle East envoy in the administrations of George H.W. Bush and Bill Clinton. He wrote "The Missing Peace," published in 2004, a lengthy account of his diplomacy that largely blamed the late Palestinian leader Yasser Arafat for not reaching a peace deal in the waning weeks of the Clinton administration.

Ross's efforts may remain hidden for some time. In an article titled "Diplomatic Strategies for Dealing With Iran," published in September by the Center for a New American Security, Ross recommended that the initial approach to Iran take place through a "direct, secret back channel."

Ross wrote that "keeping it completely private would protect each side from premature exposure and would not require either side to publicly explain such a move before it was ready. It would strike the Iranians as more significant and dramatic."