While US President Donald Trump has said he is open to sitting down with Chinese and Russian counterparts Xi Jinping and Vladimir Putin at the Apec summit, it remains far from certain that the three leaders will actually meet in a few weeks. Observers said much would depend on whether the countries could agree on an agenda, with one expert describing this as a “critical lever”. Russia was set to gain most if the trilateral meeting took place, experts said, as the summit would be a potent symbol...