President Bush, who backs U.N. sanctions against Zimbabwe, urged the international community on Monday to come together on ways to punish its president, Robert Mugabe, who is accused of using violence to win votes and quash his political opposition.

At the Group of Eight summit of industrialized nations, Bush said he is "extremely disappointed" in Zimbabwe's violence-marred presidential election. International observers say the June 27 runoff election that kept Mugabe in power was illegitimate.

"You know I care deeply about the people of Zimbabwe," Bush said. "I'm extremely disappointed in the elections, which I labeled a sham election."

Bush and the other G-8 leaders met with leaders of seven African nations on the sidelines of the summit to discuss the wealthy nations' aid to the continent, but the situation in Zimbabwe also was high on their agenda.

African nations are deeply divided, with many reluctant to put public pressure on Mugabe despite U.N. and Western calls for tough action. There was talk about sanctions and the prospects for a power-sharing arrangement in Zimbabwe, but no consensus was reached on what to do.

At a summit earlier this month in Egypt, African Union leaders adopted a resolution calling for dialogue in Zimbabwe, but did not directly criticize Mugabe or the runoff. The AU leaders said they were "deeply concerned" about the situation but their only promised action was be to support "the will" for a unity government.

Mugabe's African peers are trying to persuade the 84-year-old leader to loosen his grip and share power with his top rival, Morgan Tsvangirai, who got the most votes among the four candidates who competed in the opening round of the presidential election March 29. Tsvangirai dropped out of the runoff with Mugabe because of killings and beatings of his supporters.

Standing next to Bush, Tanzanian President Jakaya Kikwete, the current head of the African Union, said that while some African leaders share U.S. concerns, "The only area that we may differ is on the way forward."

"We are saying no party can govern alone in Zimbabwe, and therefore the parties have to work together in a government and look at the future of their country together," he said.

Bush, who saw Kikwete in Tanzania in February, said he has invited the African Union leader to come to Washington and have talks at the White House in August.