TIANJIN, China, Sept 1 (Reuters) - Chinese President Xi Jinping and Russian President Vladimir Putin pressed their vision at a regional summit on Monday for a new global security and economic order that prioritises the "Global South", in a direct challenge to the United States.

Xi was hosting more than 20 leaders of non-Western countries at a two-day summit in the northern Chinese port city of Tianjin of the Shanghai Cooperation Organisation (SCO).

The SCO must "promote the democratisation of international relations and enhance representation of developing countries", Xi said in a speech, adding that at a time of turbulence "global governance has reached a new crossroads".

"We must continue to take a clear stand against hegemonism and power politics, and practise true multilateralism," he said, in a veiled attack on the current U.S.-dominated world order.