WASHINGTON -- Democratic Reps. Tim Walz and Betty McCollum touted China's progress in climate change, human rights and the push for Tibet's autonomy Tuesday.

Walz and McCollum spent last week there on a government-sponsored trip meeting with top government officials and Tibetan leaders. They traveled with Democratic Minority Leader Nancy Pelosi and a handful of other lawmakers.

The week was spent in candid -- sometimes even heated -- discussions with the Chinese president and premier about press freedom and how China treats dissidents, the elected officials said. 

Walz, who first traveled to China back in the late 1980s as a high school teacher, said the Chinese should be commended for its "spectacular" infrastructure.

"I think China rightfully feels a sense of pride on that ... but I think it's safe to say the human rights aspects are lagging a little behind," he said. "In all fairness, I would have never imagined being in the deepest enclaves of the Chinese government having a debate about the Dalai Lama in the spirit of back and forth."

McCollum said she was sanguine about the Chinese partnership to work on climate change. The Chinese president announced at the White House in September a new national cap and trade program to start in 2017.

"The fact that the U.S. as the most developed country and China as a large developing country are coming to gether to do what we can to offset the harmful effects of carbon pollution is very, very empowering," she said.

Above: Rep. Betty McCollum spoke about the lawmakers' trip. At left is Rep. Tim Walz.