Leaders of Commonwealth countries are meeting for informal talks in Malta. On the agenda are trade, terrorism and migration. On the first day, Uganda's president rejected accusations that the arrest of his main opponent was politically motivated.

Leaders from 53 countries, mostly former British colonies, are meeting through Sunday in Malta. They are seeking agreement on trade policy before a World Trade Organization Summit next month in Hong Kong.

The Commonwealth accounts for 20 percent of global trade, and its decisions could influence the Hong Kong summit. Leaders are also discussing issues related to terrorism and migration, and the digital divide in communications.

On the first day of the meeting Friday, human rights also took center-stage. Among the leaders attending is Ugandan President Yoweri Museveni, who is under intense pressure over the military trial of his main political rival.

Kizza Besigye was charged with treason and terrorism soon after his return from exile.

British Prime Minister Tony Blair said the arrest is of great concern. He and others urged that any trial be held in a civilian court. Commonwealth Secretary-General Don McKinnon discussed the matter with the Ugandan leader.

"We met for nearly an hour, and I certainly put the case very strongly that, what is happening there is causing a lot of people to be quite disturbed and wanting to know more and wanting some answers," said Don McKinnon.

Mr. Museveni told Commonwealth leaders that taking action against those accused of terrorism was good governance and part of an open process. He defended the arrest of Mr. Besigye, rejecting suggestions that the charges and trial are politically motivated.

"Evidence has been presented," Mr. Museveni said. "You are all invited to go there and see whether these accusations are false or not. You will be there to hear with your own ears."

Mr. Museveni also said no one would stop Mr. from running in Uganda's presidential elections next year.

Mr. Besigye has been told he will remain in prison until December 19, a few days after nominations close for presidential candidates. He does not have to be physically present to be nominated.

Uganda has also been accused recently of suppression of media opposition, but Mr. Museveni denied his government restricted the media, saying journalists needed to "improve the quality" of their work.

Despite serious concerns about human rights in Uganda among Commonwealth leaders, they are not expected to take immediate action against the country, which is due to host the next summit in 2007.