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HONG KONG, May 28 (Reuters) - China is "seriously considering" restricting rare-earth exports to the United States, the editor in chief of the Chinese tabloid Global Times said on Tuesday.

Rising tensions have led to concern that Beijing will use its dominant position as a supplier of rare earths for leverage in the trade war between the United States and China.

"Based on what I know, China is seriously considering restricting rare earth exports to the U.S. China may also take other countermeasures in the future," Hu Xijin wrote on his Twitter account.

A senior official from China's state planner, the National Development and Reform Commission, said China will give priority to domestic demand but is also willing to meet reasonable demand from other countries for rare-earth resources.

Chinese President Xi Jinping visited a rare-earth company in southern China last week, according to state media reports. The price of shares in rare-earth producers gained amid speculation Xi's visit indicated China was considering using rare earths as a weapon in the trade war.

China accounted for 80% of the rare earths -- a group of 17 chemical elements used in high-technology consumer electronics and military equipment -- the United States imported from 2014 to 2017.

So far, Chinese rare-earth exports have been spared from recent tariffs by the United States, which has decided not to impose import duties on those and some other critical minerals from China as part of the trade war.

Beijing, however, has raised tariffs on imports of U.S. rare-earth metal ores from 10% to 25% from June 1, making it less economical to process the material in China. (Reporting by Meg Shen in Hong Kong and Se Young Lee in Beijing; additional reporting by Tom Daly; editing by Larry King)

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