The United Nations Security Council, chaired by Foreign Secretary Boris Johnson, observed a minute of silence at 2pm on Thursday to mark the terrorist attack in Westminster.
In New York, Mr Johnson earlier paid tribute to the “heroic” police officer Keith Palmer on MSNBC’s Morning Joe programme and said the attacker “will not prevail”.
“What I can say about the individual concerned is that his values, what he stands for, the thing he attempted to do, his idea of the world, will not prevail.
“He launched an attack on our democracy, the heart of our democracy, as has happened many times in the last decades, and the values incarnated by that Palace of Westminster will continue to triumph.
“Whatever he thought he was doing, he will not succeed,” Johnson said.