(CNN) - It's supposed to be a summit about the global economy, but the debate over possible military strikes for Syria's apparent use of chemical weapons will likely overshadow the G-20 conference this week.

The meeting in Russia will pit two leaders with polar opposite views on Syria - U.S. President Barack Obama, who wants to launch limited military strikes against the Syrian regime, and Russian President Vladimir Putin, whose country stands by its longtime ally in the Middle East.