U.S. Defense Secretary Leon Panetta signed a document?officially?ending the Iraq War on Sunday as?the last U.S. troops pulled out of?the war torn country.

U.S. Defense Secretary Leon Panetta [File photo]

Pentagon Press Secretary George Little?said that Panetta signed the document, code named EXORD 1003 Victor, Mod 9, a little before 7 a.m., which?puts an official end to the war that lasted nearly 9 years.

Before Panetta signed the official document, the last batch of U.S. combat forces?left Iraq?on Sunday morning and crossed into the neighboring country?Kuwait.

The war left about 4,500 U.S. soldiers and more than 100,000 Iraqis dead,?countless wounded and 1.75 million Iraqis displaced.

The U.S. troop withdrawal started?earlier before the Dec. 31 deadline set by U.S. President Barack Obama to fulfill his election promise to pull all the American troops out of Iraq as agreed in a security pact between the two countries in 2008.

In his weekly address on Saturday, Obama marked the end of the Iraq War, saying "Iraq's future will be in the hands of its own people. Our war there will be over.? All of our troops will be out of Iraq."