World 400m hurdles silver medalist Rai Benjamin has decided not to compete in Europe before the Tokyo Olympics in a move that wipes out a showdown with newly-minted world record holder Karsten Warholm in Monaco on July 9.

"The time is very tight - I leave for Tokyo in three weeks - so we decided not to go to Europe," Benjamin said in a statement to Reuters on Friday.

The American had run the then second fastest 400m hurdles ever in winning the U.S. Olympic trials in 46.83 seconds last month.

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But Norway’s Warholm went even faster in Oslo on Thursday, crushing Kevin Young’s 1992 world record with his run of 46.70.

"Prior to the trials, I initially planned to run in Europe in Budapest and Monaco,” Benjamin said, adding that after the trials he returned to Los Angeles to talk with his coaches.

"They decided it was best to take an easier week this week and ramp my training back up next week to be best for Tokyo," he said.

Benjamin and Warholm are expected to meet in the Olympic final.