The upcoming second high-level trade negotiations between China and the United States would probably be "quite tough", a senior analyst said Thursday, ahead of the trip to the US by Vice-Premier Liu He.

Ruan Zongze, executive vice-president of the China Institute of International Studies (CIIS), told China Daily that the trade negotiations have entered a difficult time for the two sides to reach consensus.

"The US side has asked for an extremely high price, which in my opinion is quite absurd and not constructive," he said while attending the launch ceremony for International Situation and China's Foreign Affairs, a 2018 book compiled by CIIS.

Ruan added that it's necessary for the two sides to keep coordination and negotiation over trade issues despite the disagreements.

"The two countries should find a way that could be accepted by both sides to resolve the issue," he said.

Vice-Premier Liu will lead a Chinese delegation to the US to discuss economic and trade issues at an appropriate time, following China's receipt of an invitation from US Treasury Secretary Steven Mnuchin, the Ministry of Commerce said Wednesday.

This would be the second high-level meeting since bilateral trade disputes escalated in March. The first talks took place in Beijing on May 3 and 4.

Jiang Yuechun, director at the Department for World Economy and Development of CIIS, said at the book's launch ceremony that a trade war would not only harm both China and the US but also affect many other countries.