Theresa May has become the first head of government to sign the White House guest book under US President Donald Trump.
White House press secretary Sean Spicer posted an image of the historic event on his official Twitter page.
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To be clear, this was as benign and accident-free a start to a new "special" relationship as Theresa May and her advisers could have wanted.
Voice and body language expert Caroline Goyder writes for ITV News about the signals given off during the meeting between the two leaders.
In the past, Mr Trump has described the organisation as "obsolete" and questioned the contribution of some members.