April 4 (Reuters) - U.S. high yield corporate bond

spreads surged to 401 basis points as of late Thursday, their

highest since November 2023, as global markets swooned over

fears that U.S. President Donald Trump's plan for import tariffs

would kick off a trade war.

The options adjusted spread on the ICE BofA High Yield

Index, which measures the difference in yields between junk

bonds and Treasury debt rose from 342 basis points on

Wednesday, while spreads on investment grade bonds

rose to 106 bp, the highest since August 2024, from 96 bp.