Russian President Vladimir Putin said Monday that he and President Barack Obama have a shared understanding on how to move toward a political settlement in Syria, but added that incidents like the recent downing of a Russian warplane by a Turkish fighter jet stymie broader cooperation against extremism. Putin and Obama had a half-hour meeting on the sidelines of a climate summit near Paris, and the Russian leader told reporters they discussed efforts to compile a list of extremist groups and another one of members of legitimate political opposition. Putin said “we have an understanding how we should proceed if we talk about a political settlement.