Last updated at 6.11pm: Chief Executive Tung Chee-hwa on Thursday afternoon ended days of speculation by officially announcing his resignation to the people of Hong Kong. Mr Tung told a special news conference at 5.30pm that he had formally submitted his application to resign to the Central Government in Beijing. The Chief Executive cited problems with his health as the main reason for his resignation. ?Because I have been working very hard for a long time, my health has deteriorated since late last year.? He said he decided to step down because he believed this would be in the best interests of Hong Kong. Asked by a reporter if Beijing had ordered him to step down, Mr Tung said: ?I am already 68 and feeling worn out. Long working hours, sometimes 12 or even 18 hours a day has badly affected my health.? Remaining calm and showing little emotion, Mr Tung said his time as Chief Executive had been a very turbulent seven years for the territory. ?These have been turbulent times, full of hardship for Hong Kong people. I have done my best to serve the people, and have always worked hard,?? he added. ?I owe a great debt of gratitude to Hong Kong people who have coped with very difficult times.? He said his time in office had been a unique era for Hong Kong. ?It is the first time in our history the Hong Kong people have run the territory.?? Near the end of the conference, Mr Tung said he was unable to stand up at the podium any longer due to his health problems. Asked whether the Central Government had attempted to persuade him not to resign, he said: ?I sent out the letter only one hour ago. The Central Government hasn?t approved it.? Asked about his replacement, he said, ?I hope I can get a reply [from the Central Government] as soon as possible, hopefully in a few days rather than a few weeks. If the application to resign gets approved, the Chief Secretary [Donald Tsang Yam-kuen] will act as Chief Executive until an election is held.? He was upbeat about the future of his government. ?I believe all the major officials will make their best efforts for Hong Kong and do a good job in the transitional period,? Mr Tung said. ?After serving as Chief Executive, in future... I will not work for any private companies, including my family businesses, to avoid any conflicts of interest.? ?My biggest regret is that I am not able to complete the five-year term because of health problems,? he added. Chief Secretary Donald Tsang said he would take over from Mr Tung as Chief Executive ? as outlined in the Basic Law. ?I respect Mr Tung?s decision to step down today,? Mr Tsang added.