Sept 16 (Reuters) - Here is a snapshot of Reuters news about the crisis in Syria:
* The United States, France and Britain warned President Bashar al-Assad that there would be consequences if he fails to stick to a deal under which Syria must give up its chemical weapons, and U.N. experts confirmed sarin gas was used in the Aug. 21 attack in Damascus.
* Russia, which negotiated the deal with the United States, cautioned against imposing tough penalties on the Syrian leader, who is Moscow's close ally.
* Turkish warplanes shot down a Syrian helicopter after it violated Turkish airspace and are continuing to patrol the border, Turkey's Deputy Prime Minister Bulent Arinc said.
* U.N. warcrimes investigators know of 14 potential chemical attacks in Syria since the began monitoring Syrian human rights abuses in September 2011, the team's chairman said.
* War crimes blamed on the Syrian opposition are predominantly being carried out by foreign fighters, a U.N. human rights investigator said, highlighting a deepening rift in the opposition that has been an obstacle to peace talks.
"If you're going to look for the (opposition) groups that are committing the worst crimes, look particularly for the foreign fighters, where the foreign fighters are fighting." - U.N. human rights investigator Karen Koning Abuzayd
"If Assad fails in time to abide by the terms of this framework, make no mistake, we are all agreed - and that includes Russia - that there will be consequences." - U.S. Secretary of State Kerry
"Our (European) partners want to again unilaterally review what we've agreed on with the Americans. That's not how you do business, and I'm sure that despite these statements that are coming from European capitals, the Americans will, as proper negotiators, strictly stick to what has been agreed on." -Russian Foreign Minister Lavrov
MARKETS: Stocks and bonds on major markets rallied after former U.S. Treasury Secretary Lawrence Summers withdrew from consideration to be the next chairman of the Federal Reserve, leading investors to believe U.S. monetary policy might stay looser for longer.
U.S. Secretary of State John Kerry will host China's Foreign Minister Wang Yi at a meeting and working lunch on Thursday at which Syria and North Korea will be discussed.