(Reuters) -Nvidia ( NVDA ) forecast second-quarter revenue below market estimates on Wednesday, expecting a major hit to sales from tighter U.S. curbs on exports of its AI chips to key semiconductor market China.

The artificial intelligence market bellwether expects revenue of $45 billion, plus or minus 2%, in the second quarter, compared with analysts' average estimate of $45.90 billion, according to data compiled by LSEG.