"They are developing capabilities that are very maritime focused, maritime and air focused, and in many ways, very much focused on us," he told a conference of the Navy League, a nonprofit seamen's support group, in Washington. "They seem very focused on the United States Navy and our bases that are in that part of the world."

But he said the build-up propelled by fast economic growth required the United States and allies or partners like South Korea, Japan, Australia and New Zealand to work together to "figure out a way to work with (China)" to avoid miscalculations.

Mullen's comments followed remarks by President Barack Obama's top adviser on Asia on Friday calling for high-level talks with the Chinese military to reduce mistrust.

A brief naval clash in March in waters near China underscored that "the absence of a sound relationship between our two militaries is a part of that strategic mistrust," said Jeffrey Bader, senior director for Asian affairs at the National Security Council.

Catholic and Protestant congregations will celebrate their belief in Jesus' resurrection on the same day as Orthodox churches in 2010 and 2011 because of a coincidence in the Julian and Gregorian calendars. The common holiday has happened three times this decade. But the World Council of Churches says consensus is emerging that these should not just be occasional occurrences.

At a recent meeting in Lviv, Ukraine, theologians representing nearly the breadth of Christianity agreed in principle on a strategy for all the faithful to continue observing their feast together.

"It's not a problem of principle, of dogma or of doctrine," said Juan Michel, spokesman for the council, whose 350 Protestant, Orthodox and other churches represent more than 560 million Christians. It cooperates with the Roman Catholic Church, which is not a member.

"It's more of a pastoral issue for some churches," said Michel. "There are concerns how the faithful will feel if there is a change in the traditional way of calculating the date."