Washington, June 6 -- US President Donald Trump has signed a travel ban on 12 mostly Middle East and African countries, reviving one of the most controversial measures from his first term. The move bans all travel to the US by nationals of Afghanistan, Myanmar, Chad, Congo-Brazzaville, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan and Yemen. Trump also imposed a partial ban on travellers from seven other countries: Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan and Venezuela. P2...