Chinese Vice President Xi Jinping says China welcomes the U.S. playing a “positive role” in the Asia-Pacific region. But, he said, the world's two largest economies should respect each other's “core interests and major concerns.”

In what has been billed as the major policy speech of his four-day visit, Xi addressed a luncheon in Washington co-hosted by the US-China Business Council and the National Committee on U.S.-China Relations.

A number of China's most prominent corporate leaders are accompanying Xi on his trip.

Xi also met with U.S. Congressional leaders Wednesday and travels later in the day to Iowa. He will stop in California before heading back to China on Friday.

Xi's visit is being closely watched in both countries, as he is expected to become China's Communist Party leader later this year and president in 2013.

Chinese state media have carried glowing accounts of the high-profile visit, describing the U.S.-China relationship as the most important in the world.

Vice President Xi met at the White House Tuesday with President Barack Obama and Vice President Joe Biden. The White House says specific human rights cases and the situation in Tibet were raised in the discussions.

Xi's government has been deeply embarrassed by a series of self-immolations by Tibetans protesting Chinese policies. But during his White House meetings Tuesday, Xi said his country will continue to advance the “tremendous and well-recognized” achievements on human rights he said it has made in recent decades.

But Phelim (FEE'-lim) Kine, a senior researcher at Human Rights Watch, told VOA Wednesday there was nothing new in Xi's remarks.

“Vice President Xi Jinping's comments on China's human rights situation are tried-and-true boiler plate comments, which Chinese leaders make on every visit to the United States.”

Mr. Obama assured Vice President Xi on Tuesday that the United States welcomes China's rise in the world, but said all countries must follow the “same rules” when it comes to the world economic system and human rights.

The United States is also using Xi's visit to reassure Beijing that the “pivot” in U.S. military power toward Asia is not meant to contain China's rise.

Xi was honored with a 19-gun salute when he visited the Pentagon Tuesday afternoon. Defense Secretary Leon Panetta greeted him on the building's north steps, accompanied by parading soldiers.

In an interview published Monday in The Washington Post, Xi warned against a U.S. military build-up in Asia, even while maintaining that there is “ample” room in the Pacific region for both countries.