President Donald Trump is set to impose economic sanctions on Turkey as early as this week for its incursion into northern Syria, one of the few levers the United States still has over the NATO-ally.

Tests of China's new upstream Jinghong dam on January 1 to 3 are expected to lead to a drop in the Mekong's water level by as much as one metre.

The Iranian Foreign Ministry condemned the actions as "a clear example of terrorism," and a top militia leader vowed retaliation against US forces in Iraq.

The former US vice-president has emphasised the need for a future Democratic president to work with Republicans, stressing the importance of consensus.

The verdict, which can be appealed, was the first connected to the killing of more than 200 pro-democracy protesters.