<span style="color: #222222;">US President Donald Trump has threatened a government shutdown if the Congress refuses to back major changes to immigration policies like establishing a merit-based system. </span><br />'' <br />'' <span style="color: #222222;">At a joint news conference with Italian Prime Minister Giuseppe Conte at the White House, Mr Trump said, America is the laughing stock of the world due to, what he termed, the worst immigration laws. He called to end chain migration adding that he and the Italian Prime Minister are united in their conviction that strong nations must have strong borders.</span><br />'' <br />