U.S. Democratic presidential candidate Barack Obama, center right, walks along with Afghan President Hamid Karzai, center left, and other officials at the Presidential Palace in Kabul, 20 July 2008

Afghan officials say Obama and Mr. Karzai shared lunch Sunday at the heavily-guarded presidential palace in the Afghan capital. A video of the meeting shows the men smiling and chatting in front of a fireplace, but details of their discussion were not made public.

Obama began his day eating breakfast with U.S. troops at a military camp in Kabul. There are about 35,000 U.S. troops in Afghanistan.

Obama has called for U.S. troops to be gradually withdrawn from Iraq to increase the American military presence in Afghanistan. He says Afghanistan is more important in the fight against terrorism.

The troops in Afghanistan have been fighting militants loyal to the Taliban since 2001, when a U.S.-led invasion pushed the extremist Islamist group from power.

Obama has been critical of the Afghan president's leadership, saying Mr. Karzai should do more to rebuild the country and earn the Afghan people's confidence.

Despite the criticism, Obama says he will do more listening than talking on his visit to Afghanistan.

He is traveling with two other U.S. senators, Republican Chuck Hagel of Nebraska and Democrat Jack Reed of Rhode Island. On Saturday, they were briefed by senior military commanders at the main U.S. base at Bagram. They also traveled to the eastern city of Jalalabad for talks with the provincial governor Gul Agha Shirzai, a former militant leader.

The congressional delegation also plans to visit Europe and the Middle East -- including Iraq, Israel and Jordan. Palestinian officials say Obama will also meet with Palestinian leaders in the West Bank.

Obama's Republican rival, John McCain, has criticized Obama for announcing a strategy for Iraq and Afghanistan before traveling to the countries.

Some information for this report was provided by AFP,AP.

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