Prince William and Kate have signed a book of condolence to the victims of the Pulse gay club massacre.

At least 49 people were killed and 53 were injured in the shooting at the Pulse gay club in Orlando over the weekend. With more than a hundred now confirmed dead or injured, the shooting has become the worst in American history.

Vigils have been taking place across the world, with thousands of LGBT people and allies taking to the streets to show solidarity.

Following the horrific attack, the Duke and Duchess of Cambridge visited the US Embassy in London today, to sign a book of condolence for the victims.

The pair wrote: “With our deepest condolences and with our thoughts and prayers to all those affected.”

They signed the statement “William and Catherine”.

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The book of condolence is placed in front of a flag marking LGBT rights, which was gifted to the embassy in 2012 by the Kaleidoscope Trust.

The flag was designed by American artist Sam Gassman, and features the text of a landmark LGBT rights address given by then-Secretary of State Hillary Clinton at the United Nations.

HM The Queen had already released a statement on Orlando, which said: ““Prince Philip and I have been shocked by the events in Orlando. Our thoughts and prayers are with all those who have been affected.”

Given the Monarch’s role as head of the Commonwealth – with 90% of Commonwealth citizens still living under anti-gay laws – the Royals have remained historically neutral on LGBT issues

However, barriers have slowly come down as they seek to modernise. Prince William became the first major royal to explicitly speak out against homophobia last year on a school visit, as part of an anti-LGBT bullying workshop.

Referring to a chart of how to tackle homophobia, he said: “I would start on that side [comfort the victim] and end up here [confront the bully].”

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