China's move could kick-start talks, but may also leave Mr Obama having to shoulder the blame if the Copenhagen conference ends in failure.
Mr Karzai's visit came after an attempt to kick start peace talks in the Qatari capital of Doha foundered in June.
While the official point of the visit was a cultural exchange, the actress Annette Bening said she hoped the presence of the Americans would help kick-start talks between the countries, Agence France-Presse quoted her as saying.
"You only really get kicked when you start talking about specific projects, specific roads," Laurance said.
The 15-nation UN Security Council statement on prisoners was made in the hope of kick starting peace talks between representatives of the two sides in Ethiopia.
"It's an opportunity to kick off the campaign, start talking about how we are going to change the country".
On his Sina Weibo site, a microblogger who says he is a Canadian living in Beijing commented pointedly: "Strangely, Ireland didn't freak out and start talking about kicking out foreigners".
She's very good at kicking me in the butt when I start talking negatively about the round, or my shot, or my swing.
You start talking about an ass-kicking octopus.
The latest violence comes the day before Afghan President Ashraf Ghani was scheduled to attend the Heart of Asia regional conference in Pakistan, which has been convened with hopes to kick start the next round of peace talks between regional powers and the militant group.
This producer and I start talking and four hours later we get kicked out of said bar.
