Britain's Queen Elizabeth II opened today a summit of Commonwealth leaders who called for their summit to send a clear message to next month's world trade talks in Hong Kong _ that poor countries expect the negotiations to deliver greater benefits from global markets. As many as 53 heads of government attended the summit, the Associated Press reported. Prime Ministers Tony Blair of Britain and John Howard of Australia and the other Commonwealth leaders gathered for three days of informal talks at a resort in Golden Bay on this former British colony which joined the European Union last year. The monarch, who is making her first overseas trip since the July 7 terrorist bombings in London, offered appreciation for the "many expressions of sympathy and support" which she received from Commonwealth countries after the attacks on London's mass transit system. Terrorism, migration and how to bridge the so-called "digital divide" in communications technology between developed and developing parts of the world are also on the summit agenda. Commonwealth Secretary-General Don McKinnon said the club, whose members share much of the heritage of the former British colonial empire and include developing countries in the Caribbean, Asia and Africa, should take up the cause of the poorer nations in crucial global trade talks in Hong Kong. "This is a test of Commonwealth leadership," McKinnon said. "If we can give the World Trade Organization talks the shot in the arm that it requires, then we would have shown" the Commonwealth works.