Top officials with the donor network affiliated with billionaire industrialist Charles Koch this weekend sought to distance the network from the Republican Party and President Trump, citing tariff and immigration policies and “divisive” rhetoric out of Washington.

At a gathering of hundreds of donors at the Broadmoor resort here, officials reiterated their plans to spend as much as $400 million on policy issues and political campaigns during the 2018 cycle. Earlier this year, they announced heavy spending aimed at helping Republicans to hold the Senate. But in a warning shot at Trump and the GOP, network co-chair Brian Hooks lamented “tremendous lack of leadership” in Trump’s Washington and the “deterioration of the core institutions of society.”

He called out the White House and Trump-allied GOP lawmakers, particularly over trade policy and increased federal spending, and added that “the divisiveness of this White House is causing long-term damage.”

In remarks to reporters Sunday, Koch — now solely at the helm after the retirement of his ailing brother David this year — stopped short of blaming the president personally for the political divisions.

“We’ve had divisiveness long before Trump became president and we’ll have it long after he’s no longer president,” he said. “I’m into hating the sin, not the sinner.”

Asked about Democrats possibly retaking control of the House, he said: “I don’t care what initials are in front, or after, somebody’s name. . . . I’d like there to be many more politicians who would embrace and have the courage to run on a platform like this.”

In reality, the network is expected to be a powerful force for the political right during the midterm elections, particularly in states where Senate Democrats are most vulnerable. It is also heavily backing the confirmation of federal judge Brett M. Kavanaugh to the Supreme Court. Some of the network’s biggest donors and most experienced activists are Trump’s most ardent supporters.

But some of Trump’s most ­controversial actions break sharply with the priorities of the libertarian-leaning network, which opposes Trump’s tariffs on foreign goods and his hard line on immigration, including the now-suspended zero-tolerance policy that saw hundreds of migrant families separated at the border.

And the criticism, coming just months before midterm elections in which the control of Congress hangs in the balance, was significant considering the enormous sway the Koch network has had over the years in helping the GOP gain and hold on to power.

At the three-day gathering, network leaders pointed to their recent ad campaigns thanking Sen. Heidi Heitkamp (D-N.D.) for co-sponsoring legislation that rolled back Dodd-Frank financial regulations, and attacking Rep. Lou Barletta (R-Pa.) — the Trump-backed candidate for Senate against incumbent Sen. Robert P. Casey Jr. (D) — for a vote to increase federal spending.

“I know this is uncomfortable. It was uncomfortable for me, too,” Emily Seidel, chief executive of the network’s political arm Americans for Prosperity, said in her Sunday briefing to donors. “The fact that we’re willing to do this during an election year shows everyone that we’re dead serious.”

“This network will no longer follow anyone’s lead or be taken for granted,” Seidel said, as donors applauded.

The network is holding education sessions for its activists across the country to extol the value of free trade and pro-immigrant laws, and countering Trump’s approaches on both issues. They are undertaking what officials described as a “a multiyear, multimillion-dollar commitment” to promote the benefits of free trade.

In interviews before this weekend’s confab, several donors said they are glad to see the network taking a more independent tone publicly, praising it as the type of views that attracted many of them to Charles Koch in the first place.

But some expressed anxiety about a Democratic-led House becoming reality.

“A lot of libertarians are big advocates for divided government. Divided government might end up with some resolutions for some of these issues where we’re more aligned with the other side, like enabling DACA kids to have certainty, or trade,” said Frayda Levin, a Koch donor from New Jersey. “At the same time, personally, I don’t know that I’d be happy to see Nancy Pelosi as speaker.”

Tom Shepherd, a businessman from Ohio who is a Koch donor, said, “I think that holding Republicans and Democrats accountable for decisions and votes that violate our principles is extremely helpful.”

Asked if he would stand by the network if it began endorsing Democrats or if its activities cost the GOP its House majority, Shepherd said: “Absolutely. I have no problem with it whatsoever.”

Network officials said their work on veterans’ and criminal justice issues served as a model for future policy wins, citing their willingness to work with Democrats and new allies on their priorities.

The network has met twice a year since 2003, when Koch ­convened a small group of like-minded business leaders to oppose increasing federal spending and steel tariffs under the George W. Bush administration.

Fifteen years later, the network has grown to encompass more than 700 donors who each contribute at least $100,000 annually to Koch-linked groups. More than 500 of them are gathered for the three-day retreat here at the sprawling Broadmoor resort, which encircles a man-made lake and looks out to a breathtaking view of the Rocky Mountains.

Donors also discussed the status of the network’s work on a range of priorities for the constellation of Koch-aligned groups, including free speech on college campuses, supporting anti-poverty programs in communities, conducting new research in an effort to reduce recidivism rates, and more.

The Washington Post and other news outlets were invited to cover portions of the weekend gathering on the condition that they not identify donors in attendance without their permission.

Officials said the meeting this weekend is the largest summer gathering of like-minded donors, with 135 first-time participants. Among the Republican elected officials in attendance are Sens. John Cornyn (Tex.) and Tim Scott (S.C.), Reps. Marsha Blackburn (Tenn.) and Douglas A. Collins (Ga.), Florida Gov. Rick Scott, Kentucky Gov. Matt Bevin and Nevada Attorney General Adam Paul Laxalt.

It’s the first such meeting after the June retirement of David Koch — the other half of the “Koch brothers” who have become household names — from business and political life because of his declining health.

Against the backdrop of the Rockies, Charles Koch signaled to donors sipping on cocktails and wine during Saturday’s lakeside reception that he’s here to stay.

“We’re just getting started, because we have more opportunities in front of us than I ever imagined,” he told them. “I assure you, I am not getting weak in the knees.”

James Hohmann contributed to this report.