FACTBOX: Petraeus faces broader challenges as Centcom chief

(Reuters) - Army Gen. David Petraeus would become responsible for challenges to U.S. military interests across a huge region stretching from Kenya to Kazakhstan if confirmed by the Senate as the new head of U.S. Central Command.

The Tampa, Florida-based operation, known in military parlance as Centcom, oversees hot wars in Iraq and Afghanistan and monitors tensions with Iran and Syria and instability in Lebanon.

Centcom is one of nine U.S. combatant commands -- headquarters that have responsibility for regions of the world or major military assets.

Centcom's area of responsibility covers 27 countries in Africa, the Middle East and Central and South Asia. Its operations encompass 208,000 personnel from the Army, Navy, Marines, Air Force and Coast Guard.

Its responsibilities for Africa, including Somalia and Sudan, are due to be assumed by a new headquarters for Africa, called U.S. Africa Command, which is scheduled to become fully active this autumn.

Following are some of the biggest challenges facing the U.S. military in Centcom's area of responsibility:

* Iraq: The United States has about 155,000 troops in Iraq as it tries to withdraw combat forces while maintaining a fragile stability. The force level is expected to drop to 140,000 troops by late July but the Bush administration says further reductions hinge on Iraqi political reconciliation and the ability of Iraqi forces to assume security duties;

* Afghanistan: The United States has increased its presence in Afghanistan to about 33,000 troops, adding more than 2,000 Marines to the volatile south where NATO forces are combating a stubborn Taliban insurgency. Afghanistan has seen violence rise in recent years to the highest level since U.S.-led forces ousted the Taliban government in 2001 after the September 11 attacks;

* Iran: The United States and Iran are locked in a war of words over Western claims that Tehran is pursuing nuclear arms under the guise of a civilian energy program and U.S. allegations that Iran is supplying Iraqi Shi'ite militants with weapons and training for attacks on U.S. forces. Iran denies it wants nuclear weapons and blames violence in Iraq on the presence of U.S. troops. Tensions between the two countries are also strained by recurring speculation about possible U.S. military action against the Islamic Republic;