NEW YORK >> The war of words intensified between two titans in Republican politics today as President Donald Trump trashed the conservative billionaire Koch brothers as a “total joke in real Republican circles.”

The presidential insult followed a weekend gathering of Koch officials who repeatedly condemned Trump’s trade policies, the explosion of government spending under his watch and his divisive tone.

The intra-party feud could hurt the GOP in this fall’s midterm elections and beyond. While the Kochs refused to endorse Trump’s first presidential run, the president’s loyalists don’t want his 2020 re-election campaign bogged down by lingering bad blood. The Koch network boasts an army of grassroots activists across 36 states and has promised to spend between $300 million and $400 million on politics and policy this election cycle alone.

“The globalist Koch Brothers, who have become a total joke in real Republican circles, are against Strong Borders and Powerful Trade,” Trump tweeted. “I never sought their support because I don’t need their money or bad ideas.”

The president later added: “I’m for America First & the American Worker — a puppet for no one. Two nice guys with bad ideas.”

Over the weekend, network patriarch, 82-year-old Charles Koch, refused to criticize Trump personally when The Associated Press asked whether the president should bear any responsibility for the divisive tone in Washington.

“We’ve had divisiveness long before Trump became president and we’ll have it long after he’s no longer president,” Koch said during a rare question-and-answer session with reporters. “I’m into hating the sin and not the sinner.”

Responding to Trump’s social media attack, Koch spokesman James Davis was measured. “We support policies that help all people improve their lives. We look forward to working with anyone to do so,” he said.

The day before, the Kochs’ political advocacy network announced it would not back the GOP candidate in the North Dakota Senate race, determining that Republican challenger Kevin Cramer’s record on government spending made him no better than Democratic incumbent Sen. Heidi Heitkamp in the marquee Senate contest.

The Kochs have not ruled out similar moves in top-tier Senate races in Indiana, Missouri, Montana, and West Virginia, although they are actively working to help elect Republican Senate candidates in Florida, Tennessee and Wisconsin.

“We’ve got a message for lawmakers across the country. We are raising the bar, raising expectations,” Koch lieutenant Emily Seidel told donors Monday.

While the move echoed across the political world, Republican operatives quietly dismissed the practical impact of the Koch’s decision on the North Dakota Senate race, where Cramer’s campaign believes he has a double-digit lead in the deep-red state against the Democratic incumbent. Yet there is a desire for the Kochs to cooperate with Trump allies in other states, such as Nevada and Montana, where Republican candidates are considered more vulnerable.

Some Trump loyalists were furious at perceived contradictions in the Koch network’s behavior and worried that it could complicate the president’s 2020 re-election.

“The Kochs had zero to do with Trump’s win in 2016,” former White House counselor Steve Bannon told the AP. “But they were willing to support the tax cut and the deregulation, while opposing the heart of Trumpism — trade and immigration.”

Trump’s animosity toward the Koch brothers, like so much of his anger toward conservative heavyweights, stems from the influential donors’ pointed refusal to support him in the run-up to the 2016 presidential campaign. Back then, he criticized Koch-backed politicians as “puppets.”

Tensions remained between the two camps — in part fueled by the Kochs’ status as key members of the Manhattan donor network, a group that has long rejected Trump, even as the president staffed his administration with a number of Koch alumni.

Trump has complained to confidants that the Kochs “never respected” him and “refused to get on board” his electoral movement, according to a person familiar with his views but not authorized to discuss private conversations. He has expressed worry that they may try to undermine his administration, the person said.

The president’s slam against the Koch network came shortly after the departure from the White House of legislative affairs director Marc Short, who was a top Koch network official before joining the administration.

Vice President Mike Pence, another close Koch ally, has so far been silent on the feud. His office did not respond to a question about Trump’s Twitter attacks.

“Their network is highly overrated,” Trump charged. “I have beaten them at every turn.”