By Stephen Nellis and Karen Freifeld

WASHINGTON (Reuters) -The U.S. Commerce Department should add Chinese memory chip maker Changxin Memory Technologies (CXMT) to a trade blacklist after Beijing earlier this week banned the sale of some chips by U.S.-based Micron Technology Inc, the chair of the U.S. House of Representatives' committee on China said on Tuesday.

The restrictions this week by China's cyberspace regulator against Micron, the biggest U.S. memory chipmaker, are the latest in a widening trade dispute between the world's two largest economies.

"The United States must make clear to the PRC (People's Republic of China) that it will not tolerate economic coercion against its companies or its allies. The Commerce Department should immediately add ChangXin Memory Technologies to the entity list and ensure no U.S. technology, regardless of specifications, goes to CXMT, YMTC, or other PRC firms operating in this industry," Representative Mike Gallagher said in a statement.

YMTC, which refers to Yangtze Memory Technologies Corp, is a Chinese chipmaker put on the entity list December 2022.

The powerful lawmaker also added that the Commerce Department must ensure "no U.S.-export licenses granted to foreign semiconductor memory firms operating in (China) are used to backfill Micron, and our South Korean allies, who have experienced exactly this kind of CCP (Chinese Communist Party) economic coercion firsthand in recent years, should likewise act to prevent backfilling," Gallagher said.

A representative for CXMT could not be immediately reached for comment.

Korea's Samsung Electronics Co Ltd and SK Hynix both operate memory chip factories in China. Those companies and other non-Chinese firms were spared the brunt of U.S. export controls on chip manufacturing gear imposed in October, but they are operating under exemptions from the U.S. rules that can expire or be revoked.

CXMT is China's most advanced maker of dynamic random-access memory (DRAM) chips. Analysts believe it is two to three generations behind industry leaders Micron, Samsung and SK Hynix.

Gallagher's call comes weeks after U.S. makers of chipmaker equipment say they received a clarification from U.S. export control authorities that will allow them to ship more tools to China than initially anticipated.

Lam Research Corp, the leading maker of tools for manufacturing memory chips, told investors the clarification could result in hundreds of millions of dollars in additional sales from China.

The clarification from the Commerce Department concerned how memory chip features will be measured for the purposes of applying export control rules. The looser implementation came after a group called the Coalition of Semiconductor Equipment Manufacturers started lobbying last year, according to two sources familiar with the matter.

Some of the coalition's lobbyists have also done work for Lam Research, according to lobbying disclosure records.

A Commerce Department spokesperson declined to comment. Lam Research and the lobbyists representing the coalition did not immediately respond to a request for comment.

(Reporting by Chris Sanders and Rami AyyubEditing by Chris Reese and Anna Driver)