President Barack Obama's push at the G-20 Summit for international support for U.S.-led military action in Syria failed to achieve a major breakthrough on the issue, NBC News reported. During a tense four-hour working dinner of world leaders in St. Petersburg on Thursday night, the president stressed the need to uphold the international ban on chemical weapons and assured that he has "high confidence" that Syria used poison gas against its own people on Aug. 21. Italian Prime Minister Enrico Letta tweeted that "divisions about Syria were confirmed." Obama met with Chinese President Xi Jinping early Friday, but there was no mention of Syria after their meeting. Meantime, Russia announced it was sending another warship to the Mediterranean Sea, according to state news agency Interfax, further raising the stakes for the United States.