Top Republican says Trump vows to ‘destroy’ IS before leaving Syria

Another prominent critic of the move was retired US army general Stanley McChrystal, the former commander of US and international forces in Afghanistan.

On Sunday, he told ABC that the dual drawdowns could seriously weaken US influence in the region.

“We have a tumultuous regime or region (in Syria) that now has a Russian presence which had been out for about 30 years,” he said.

“Iran has increased influence across the region now. If you pull American influence out, you’re likely to have greater instability.”

Similarly, he said, Trump’s planned drawdown in Afghanistan could seriously undercut American leverage there.

“Just when we were starting to sit down with the Taliban, just as we were starting to begin negotiations, he basically traded away the biggest leverage point we have,” McChrystal added.