Two Chinese and US nuclear companies on Tuesday (US time) signed a memorandum of understanding in Seattle, Washington to cooperate on developing and commercializing traveling wave reactors (TWR), according to a statement.

China National Nuclear Corp and US-based Terra Power LLC plan to work together to complete TWR design and make the technology for commercial use, CNNC said in a statement on its website Thursday.

The statement noted the memorandum was made possible under policies and agreements for cooperation by the governments of the US and China, and it is a milestone.

Such cooperation "will speed technology development, promote clean energy growth, and enable economic growth in both countries," the statement said. 

According to media reports, this was the first time the US and Chinese governments had authorized such cooperation on nuclear technology since the two countries signed an agreement for nuclear energy cooperation in 1985.