UPDATE 1-U.S. officials to prod China on climate change

(For a FACTBOX on U.S.-China trade, click on [ID:nN11262])

* U.S.-China action seen vital to address climate change

* U.S. companies eye clean energy tech sales to China

* China resisting hard caps on its emissions (Adds U.S. energy official in paragraphs 13-17)

By Doug Palmer

WASHINGTON, July 12 (Reuters) - U.S. Energy Secretary Steven Chu and Commerce Secretary Gary Locke visit their ancestral homeland this week to press China to join with the United States in stepped-up efforts to fight global warming.

The two Chinese-American cabinet officials arrive in Beijing on Tuesday to talk with senior Chinese leaders and highlight how working together to cut greenhouse gas emissions would benefit both countries and the entire planet.

The trip also sets the stage for a visit by President Barack Obama to China later this year that many environmental experts hope will focus on the need for joint U.S.-China action before a meeting in Copenhagen in December to try to forge a global deal on reducing the emissions.

They believe cooperation, perhaps even a bilateral deal, between the world's largest developed country and the world's largest developing country is vital if efforts to forge a new global climate treaty are to succeed.