James Bays, Al Jazeera's correspondent in the Afghan capital, Kabul, said it is likely Karzai will discuss with Obama a string of Nato offensives that have resulted in civilian casualties.
"I think Karzai is going to make it clear that mistakes by Nato and the Americans are not acceptable. He says that each time there is a civilian casualty it just adds to the support for the Taliban," Bays said.
"In the last few days, Karzai went to the scene of an incident where there were civilian casualties at a wedding party in the east of Afghanistan, to console survivors and give compensation from the government. I think civilian casualties will be on the agenda."
Obama, for his part, is expected to raise the issue of the quality of leadership in Afghanistan, Bays said.
"Obama has been critical in the past of Karzai and the Afghan government. This is a government that many in the international community see as having too many corrupt elements to it.
"I think he will ask Karzai to do more to take control of the situation."
Call for action
At the Bagram base, north of Kabul, military leaders on Satruday told Obama and the other senators travelling with him about efforts to combat Taliban forces and other fighters.
The congressional delegation then met more US soldiers at Jalalabad air field, as well as the governor of Nangahar province.
Obama has said that Afghanistan is the central front in the so-called "war on terror," and he is expected to call for more US action to rout the Taliban and al-Qaeda.
Obama has said that if he wins the US presidency in November he will commit at least two more combat brigades to Afghanistan while reducing the number of US forces in Iraq.
Bays said that if Obama is elected president and takes office in January 2009, then the Afghan elections will be one of his priorities because Karzai is also facing elections in the next year.
John McCain, Obama's Republican rival, has criticised the Democratic nominee's lack of experience in the region and on Saturday he mocked his current trip.
"Senator Obama announced his strategy for Afghanistan and Iraq before departing on a fact-finding mission that will include visits to both those countries," he said in a radio address.
|Obama says Afghanistan is the central front in the so-called war on terror [AFP]
"Apparently, he is confident enough that he will not find any facts that might change his opinion or alter his strategy. Remarkable."
Speaking on the jet before it landed in Afghanistan, Obama said: "I am there to listen, but there is no doubt that my core position, which is that we need a timetable for withdrawal, not only to relieve pressure on our military but also to deal with the deteriorating situation in Afghanistan and to put more pressure on the Iraqi government."
Obama said that it was time to respect the wishes of Iraq as a sovereign government and start withdrawing troops. A move he said, is in the strategic interests of the US.
In an interview with German news weekly Der Spiegel
on Saturday, Nuri al-Maliki, Iraq's prime minister, backed the Democratic nominee's plan to pull out US troops.
"We feel that this would be the right timescale for withdrawal allowing for minor adjustments," he said in the interview to be published on Monday. US forces should leave the country "as soon as possible," al-Maliki said.
It follows an agreement between him and George Bush, the US president, to set only a "general time horizon" for military withdrawal as part of a long-term security pact.