Prime Minister David Cameron has written to King Salman of Saudi Arabia. He said:
Your Majesty,
I was shocked and saddened to hear of the terrible events in Mecca on Thursday. My sympathies and prayers are with the families of those affected. The scale of the tragedy at such an important time in the Islamic calendar is hard to comprehend.
My thoughts and the thoughts of the British public are with you at this difficult time.
The Foreign Secretary has also made a statement expressing his condolences.