Complaints about human rights problems also will get an airing at the three-day closed-door summit.
Queen Elizabeth II opened the meeting of 53 Commonwealth nations with an appeal for determined action against challenges such as terrorism that she said posed a threat to all.
Dressed in cherry-red coatdress and broad-brimmed hat with a feather, the queen said the club of mostly former British colonies can be "strong and effective" in addressing problems such as terrorism and poverty as it is a diverse group of nations representing many faiths, cultures and people.
"Determined and collective action can also help us tackle other challenges that cannot be addressed alone, such as the scourge of terrorism, which is a threat to us all and has directly affected a number of our countries," the
British monarch said at the opening ceremony held at a conference center in the Maltese capital, Valetta.
Queen thankful
She expressed thanks to Commonwealth nations who stood by Britain in the wake of the July 7 bombings that killed 56 people on three London underground trains and a bus, the worst terrorist attack in Britain.
Other than Britain, Pakistan, India, Kenya, Tanzania, Bangladesh and Sri
Lanka are among the Commonwealth countries also struggling with terrorism.
The queen said that last year's tsunami disaster in Asia and the October 8 earthquake in Pakistan that killed more than 73,000 people underscored the importance of solidarity among Commonwealth members.
"These times of trial have brought us together as they have also shown how vulnerable we can be alone and yet how much more we can do together," she said.
Turning to poverty, the queen noted that while there had been progress in achieving the UN millenium development goals, which seek to halve poverty by 2015, there was "greater and more sober recognition that much still remains to be done if the goals are to be achieved by 2015."
"There are development challenges that weigh heavily upon so many of our members. It is our collective responsiblity to help," she said.
The 53-nation Commonwealth represents 1.8 billion people or 30 percent of the world population, with member-states in the Americas, Asia, Africa, the Caribbean, Europe and the South Pacific.
Founded in 1887 as the colonial conferences, the Commonwealth decided to begin holding regular meetings of heads of state and government at its 1971 meeting in Singapore.
Corruption call
Meanwhile Nigerian President Olusegun Obasanjo has called on Commonwealth countries to embrace a "zero tolerance" policy toward corruption in a bid to fight poverty and political instability.
CHOGM, which includes a number of nations affected by corruption, will hold a "lively debate" on the issue during a three-day summit in Malta, he told its opening session.
"Corruption has been one of the major sources of under-development, instability, conflicts, illegitimisation of leadership and government structures," said Mr Obasanjo, who hosted the last Commonwealth summit in the Nigerian capital Abuja in 2003.
After that Abuja summit, Mr Obasanjo recalled, a group of Commonwealth experts recommended "that Commonwealth countries should sign, ratify and implement the United Nations convention against corruption as a matter of urgency."
The experts also urged "clear and strong sanctions against the misuse of public funds and increased cooperation in every respect among nations in tackling corruption," Mr Obasanjo said.
"In Nigeria, we're currently engaged in a determined crusade against corruption," he said.
"We need to adopt a zero tolerance policy toward" corruption.
He said Commonwealth Secretary General Don McKinnon would be presenting the summit with "proposals aimed at facilitating the recovery of stolen assets and their return to their country of origin."