Donald Trump has once again started tweeting about the controversial "travel ban" he tried to put in place easier this year.

In four separate tweets, the US President discussed one of his flagship policies which has been regularly blocked by courts across the US since it was proposed in January.

He wrote: "People, the lawyers and the courts can call it whatever they want, but I am calling it what we need and what it is, a TRAVEL BAN!"

He then went onto say that the Department of Justice (DOJ) should have kept the original executive order that was signed in January, rather than the watered down version that was released afterwards.

He suggested the the DOJ should call for an expedited hearing with the Supreme Court before proceeding with a "much tougher version."

Concluding his quartet of tweets, he said: "In any event we are EXTREME VETTING people coming into the U.S. in order to help keep our country safe. The courts are slow and political!"

When journalists asked the White House press secretary Sean Spicer about the ban in January, he responded by saying: "It's not a Muslim ban. It's not a travel ban."

Trump said on Sunday evening (4 June) that he would do whatever was necessary to tackle terrorism in the wake of the London Bridge attack.