The president-elect said he would bring all three territories under U.S. control through economic coercion, but did not rule out using force to seize Greenland and the canal.

But the debate has raised questions about how terminally ill people could be safeguarded and coercion avoided - with criticism of the proposal coming from both Labour and Conservative politicians.

Lord Thomas, former Lord Chief Justice, told the BBC's Today Programme that it cannot be a "rubber stamping process" and judges must be satisfied there is no coercion.

When a reporter asked him whether he’d commit to not using “military or economic coercion” to achieve these goals, he immediately answered: “No.”

When a reporter asked Trump on Tuesday whether he would commit to not using “military or economic coercion” in Panama or Greenland, Trump’s answer came swiftly: “No.”