CNBC's Jim Cramer said Wednesday that U.S. companies vulnerable to a stronger dollar should be careful as their troubles may continue for a long time.
"When I hear the ECB program goes on, what you should be thinking is [that] all these companies that have problems with a strong dollar [such as] Delta" should watch out, Cramer said on CNBC's "Squawk on the Street." "Your problems may not be over."
Cramer made his remarks after the European Central Bank kept interest rates unchanged at 0.05 percent and said it would continue to move forward with its 1.1 trillion euro ($1.2 trillion) quantitative easing program.
"You keep that program going, you're going to take that euro to a much lower level," Cramer added.
Delta reported first-quarter earnings of 45 cents per share, slightly above Wall Street's estimates. Nevertheless, the airline added that the strong dollar was presenting headwinds for its revenue abroad.
Shares in Delta were up 4 percent late morning Wednesday.
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The euro was down about 0.04 percent at $1.0611 against the greenback. The common currency has shed nearly 12.5 percent against the dollar this year, according to FactSet.