President Tony Tan Keng Yam has written to Saudi King Salman to convey his condolences on the crane collapse, the Ministry of Foreign Affairs said in a statement yesterday.

"I am greatly saddened to learn of the tragic loss of lives and injuries to pilgrims caused by the crane accident at the Grand Mosque in Makkah on 11 September 2015," Dr Tan said in the letter dated Sept 12.

"On behalf of the people of Singapore, I extend our deepest and heartfelt condolences to Your Majesty and the people of Saudi Arabia.

"Our thoughts and prayers are with the victims' families during this difficult time. We also hope for the speedy recovery for those who are injured," he wrote. Dr Tan expressed confidence that the Saudi haj authorities would overcome this tragedy and do their best to ensure the safety of the millions of pilgrims.