Republican presidential front-runner Donald Trump said on Wednesday that women who end pregnancies should face some sort of punishment if the United States bans abortion, but appeared to walk back on his comments after their release by MSNBC to say the abortion issue should be handled by the states.

In a clip of an interview with MSNBC that aired Wednesday, Trump said even if abortions are banned, some women would access the procedure illegally.

"There has to be some form of punishment," he said in the excerpt. Asked what form of punishment he would advocate, Trump said, "That I don't know."