File photo of Martin Dempsey. Martin Dempsey assumed the role of top U.S. commander overseeing both the Iraq and Afghanistan wars Friday, replacing William J. Fallon as the head of the U.S. Central Command (Centcom). Photo Gallery>>>

    WASHINGTON, March 28 (Xinhua) -- Martin Dempsey assumed the role of top U.S. commander overseeing both the Iraq and Afghanistan wars Friday, replacing William J. Fallon as the head of the U.S. Central Command (Centcom).

    Although it is unclear whether the new assignment is temporary or permanent, Dempsey will be in the position for some time, according to wire and TV reports.

File photo of William J. Fallon. Fallon resigned Tuesday amid media reports that he was at odds with the White House over Iran. Dempsey used to be his deputy. Photo Gallery>>>

    Fallon resigned Tuesday amid media reports that he was at odds with the White House over Iran. Dempsey used to be his deputy.

    U.S. President George W. Bush is not expected to nominate a permanent successor to Fallon until David Petraeus, top U.S. commander in Iraq, submits reports on Iraq to Congress on April 8-9.

    It looks very likely that Dempsey could stay in the new post, but other candidates are also in Bush's mind, including Petraeus.

    Born in 1952, Dempsey's military career spans over three decades.

    He was the commander of the 1st armored division in the early stages of the Iraq war and was promoted to Centcom deputy commander last year.

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