China and the United States can overcome their differences and get relations back on track if they work together in a spirit of mutual respect, Chinese Premier Li Keqiang told a group of visiting U.S. politicians on Thursday.

China and the United States are locked in an increasingly bitter trade war, with both countries have already placed tariffs on some of each others imports.

Meeting a group of Republican senators and one congresswoman in Beijing, Li said that over the past four decades of diplomatic ties, the China-U.S. relationship has had its "share of ups and downs".

"The sound and stable growth of China-U.S. relations serves the common interests and the fundamental interests of the people of our two countries," Li said.

"We do hope that China and the United States will meet each other halfway and work together in the spirit of mutual respect and equality," he added.

"In this way, our two countries will be able to overcome differences and have the wisdom to overcome the obstacles and move our relationship forward on an even sounder track."

Tennessee Senator Lamar Alexander told Li that the delegation was there "to show our respect to a great country and a great people".

"Your country and our country are competitors but not adversaries. And we believe that with mutual respect we can continue to prosper together."

Alexander said he would be discussing trade with Li, though neither of them mentioned the ongoing tariff war in remarks in front of reporters.

U.S. President Donald Trump has long threatened to impose tariffs on all $500 billion-plus goods imports from China if Beijing fails to meet his demands for sweeping changes to its policies on intellectual property, technology transfers, industrial subsidies and local market access.

But Trump has not "set in stone" any decisions on escalating tariffs on Chinese goods and may withdraw some duties if there are promising policy discussions with China, White House economic adviser Larry Kudlow said on Wednesday.

Both Trump and Chinese President Xi Jinping are due to attend the G20 summit in Argentina which starts at the end of this month, and could hold talks there.

Trump said in a television interview on Monday he thinks there will be "a great deal" with China on trade, but warned that he has billions of dollars worth of new tariffs ready to go if a deal isn't possible.

The United States has already imposed tariffs on $250 billion worth of Chinese goods, and China has responded with retaliatory duties on $110 billion worth of U.S. goods.