Presidential candidate Donald Trump refused on Sunday to apologize for his remarks about the war record of U.S. Sen. John McCain despite a growing firestorm among fellow Republicans, and said he had no plans to drop out of the race.

Asked on ABC's "This Week" if he owed McCain an apology for saying the former prisoner in North Vietnam was only considered a war hero because he was captured, Trump said, "No, not at all." He again blasted McCain's support for fellow veterans.

"John McCain has failed," Trump said, citing delays in health care for veterans. "I believe that I will do far more for veterans than John McCain has done for many, many years, with all talk no action ... Nothing gets done."