US President Donald Trump has said he is not aware of any invitation to the royal wedding of Prince Harry and Meghan Markle.

In his address at the World Economic Forum, US President Donald Trump on Friday pitched the overhaul of the immigration system pushed by his administration "as a matter of both national and economic security" and made a pointed reference to the extended family chain migration.

US President Donald Trump said on Friday that US-backed coalition forces had won back almost 100 percent of territory occupied by ISIS in Iraq and Syria.