Chief Executive Donald Tsang has called on World Trade Organisation key players to resolve their differences to achieve a breakthrough in the Doha Development Agenda negotiations.

Speaking at the Asia-Pacific Economic Co-operation Economic Leaders' meeting in Sydney today, Mr Tsang said Hong Kong will participate actively in the negotiations and it looks forward to substantive and intensive discussions in the WTO meetings in September and beyond.

Hectic schedule: Chief Executive Donald Tsang is greeted by Australian Prime Minister John Howard before joining the APEC Business Advisory Council meeting. He poses for a group photo with other APEC economic leaders at the Sydney Opera House before joining President Hu Jintao at the 15th APEC Economic Leaders' Meeting.

Noting bilateral and regional free-trade agreements are no substitute for the multilateral trading system, Mr Tsang said there is nothing one can do on an individual basis that can create a better trading environment than the Geneva-based system, which applies multilaterally.

On coping with the harmful effects of climate change, the Chief Executive said it will be a team effort requiring close collaboration at all levels.

"Member economies should convey a clear and strong message to the business community that they need to factor core environmental values into their business decisions. We should also drive home the message that every individual can and must play a part in protecting the environment.

"We welcome the proposed Declaration on Climate Change, Energy Security & Clean Development. The initiatives set out in the Action Agenda to strength cooperation in areas such as energy efficiency, forest cover, energy research and bio-fuels should go a long way to enhancing APEC economies' capacities to make positive responses to the challenges posed by climate change," Mr Tsang added.

He pointed out that efforts must be stepped up to raise the "sinks" of greenhouse gas emissions in the world by properly maintaining, managing and nurturing forest resources. Hong Kong has planted more than 11 million trees over the past five years and plans to do more in the future.

Mr Tsang had a packed schedule today. Earlier in the morning, he joined other economic leaders to meet APEC Business Advisory Council members to exchange views on ways to further APEC's work. In the evening, he attended the official dinner hosted by Australian Prime Minister John Howard.

Tomorrow, Mr Tsang will attend the ongoing APEC Economic Leaders' Meeting.