Atlanta (CNN) Donald Trump slammed GOP leaders on Wednesday for not lining up behind him, implying that he's willing to go forward without their help.

"We have to have our Republicans either stick together or let me just do it by myself. I'll do very well. I'm going to do very well. OK? I'm going to do very well. A lot of people thought I should do that anyway, but I'll just do it very nicely by myself," Trump said, though he did not elaborate on what doing it "by myself" would mean.

The presumptive Republican presidential nominee also accused his party's leaders of being weak and told them to "please be quiet."

"You know the Republicans, honestly folks, our leaders, our leaders have to get tougher," Trump said during a rally in Atlanta. "Our leaders have to get a lot tougher. And be quiet. Just please be quiet. Don't talk. Please be quiet. Just be quiet to the leaders because they have to get tougher, they have to get sharper, they have to get smarter."

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