U.S. Sen. David Perdue says his close ties to President Donald Trump will not prevent him from being impartial should the House file impeachment charges that require a Senate vote.

Trump is raising money with Perdue on Friday, and last week the senator accompanied the president at the World Series. Perdue has also panned the House's impeachment probe, saying there is no evidence Trump did anything wrong and that the president has been treated unfairly.

But that doesn’t mean he won’t weigh all the evidence and make a fair decision if the Senate has consider charges against the president, Perdue told The Atlanta Journal-Constitution on Monday.

“My oath of office says I am to uphold and protect the Constitution of the United States; that’s what I intend to do,” he said. “And what's not being done right now in the House is those guys I don't believe they’re upholding that oath because if you listen to the Constitution then this person should be given due process.

“So, I will be very objective; I've been objective. I've seen all the evidence that they're looking at right now and nothing rises to the level of impeachment.”

Perdue’s opponents have accused him of making up his mind that the Democrat-led House is wrong about Trump even though the investigation has not wrapped up.

“Perdue’s obligation is to withhold judgement until evidence is presented in full,” Democrat Jon Ossoff said in a statement. “But he’s one of Trump’s most servile underlings, so he’s already proclaimed the President innocent. Even some of Perdue’s wiser Republican colleagues are waiting for the evidence.”

After House Democrats introduced legislation last week outlining the next steps for their impeachment probe, Perdue wrote on Twitter that, "This changes nothing. Still no due process. Still totally unfair. It's a sham show trial and nothing more."

Another of his opponents, Clarkston mayor Ted Terry, quipped in response that the tweet seemed to be written by Trump himself.

Read more | Ga. lawmakers vote with parties to set rules for impeachment inquiry

Also | Trump’s Atlanta trip Friday aims to defend David Perdue