US President Donald Trump's order banning citizens of 12 nations from entering the United States has come into effect on Monday. The countries affected by the travel ban are Afghanistan, Myanmar, Chad, Republic of the Congo, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan and Yemen.The move is expected to disrupt refugee pathways and further restrict immigration as the Trump administration expands its crackdown on illegal entries.In announcing his restrictions last week, Trump said the new measure was spurred by a recent terrorist attack on Jews in Colorado.The group had been protesting in solidarity with hostages held in Gaza when they were assaulted by a man the White House said had overstayed his visa.That attack, Trump said, underscored the extreme dangers posed to our country by the entry of foreign nationals who are not properly vetted or who overstay their visas.The president calls the move as protecting the country from foreign terrorists. The entry of people from seven other countries, including Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan and Venezuela has been partially restricted.Trump said the countries that face the ban were harbouring a large-scale presence of terrorists, fail to cooperate on visa security, have an inability to verify travelers' identities, and have an inadequate record-keeping of criminal histories. He added that citizens of these countries also have a high rate of visa overstays in the US. The travel ban is a part of the president's attempts to restrict immigration into the US. However, the ban will not apply to athletes competing in the 2026 FIFA World Cup, which the United States is co-hosting with Canada and Mexico, or in the 2028 Los Angeles Olympics. It will not apply to diplomats from the targeted countries either.