Obama says Iran should take U.S. seriously

Envoys from the United States, Russia, China, France, Germany and Britain -- the so-called sextet of world powers -- attended the Geneva meeting.

"I want the Bush administration to be successful in working with the Europeans to get Iran to stand down on its nuclear weapons program," Obama said.

Iranian President Mahmoud Ahmadinejad was quoted on Iranian state television saying his country has more than 5,000 active centrifuges for enriching uranium, suggesting a rapid expansion of nuclear work.

IMPRESSIONS OF MALIKI, KARZAI

Also in the Reuters interview, Obama talked of his impressions of Iraqi Prime Minister Nuri al-Maliki and Afghan President Hamid Karzai, both of whom he met during the trip.

"I think Maliki has made some tough choices, particularly going into Basra and Sadr City to disperse the Shia militias. I'm glad to see that he is eager to take more responsibility for his country's own security," Obama said.

"I think he recognizes that the Iraqi government both has to become more efficient and more inclusive. Whether he understands the degree to which that has to happen ... I can't tell," he added.

The Democratic candidate said Karzai is "very smart and charming" and has a vision for Afghanistan's future. But he said he needed to move to rid his government of corruption and combat the narcotics trade.

"I told President Karzai that I thought that he needs to really focus on issues of corruption and counternarcotics and to counter the narcotics trade much more aggressively than has been done so far," he said.