President Donald Trump defended his Justice Department's indictment of former FBI director James Comey Friday and said, "there will be others."

Speaking to reporters on the White House South Lawn as he departed for the Ryder Cup, the president dismissed suggestions that Comey was being charged as part of a broader retribution campaign.

Still, he warned, there will be more.

"It's not a list, but I think there'll be others," the president told reporters on Friday as he departed the White House.

Trump said "these were corrupt, radical-left Democrats" and accused his political opponents of weaponizing the Justice Department. (Comey had long been a registered Republican.)

Saying "I hope" others will be charged, Trump also brushed aside concerns that a future Democratic administration could use its powers to go after Trump and his allies.

"Well, that's what they tried to do, right? They did it with me for four years, they went after me," Trump said. He later added: "It's about justice, it's not revenge."