Cloud was due to make the fifth defence of the title he won against Britain's Clinton Woods in 2009, but Pascal has pulled out with a hand injury - he has suffered a bone bruise.
Pascal is the former WBC champion but has fought just once in 18 months, in a rematch with Bernard Hopkins last May when the veteran became the oldest-ever world champion at 46 with a narrow points win. It was the second defeat of Pascal's career, the first having come at the hands of Briton Carl Froch.
It is another disappointment in the career of the unbeaten Cloud, who claims he is avoided by the big names at 175lbs.
It is hoped the match-up with Pascal can be re-arranged for October.