CONCORDGov. Chris Sununu came out strongly Thursday in opposition to a proposed rule that would permit Republican Party leaders to choose sides in future primaries.

Bruce Breton of Windham, an active supporter of President Trump in 2016, decided against running for vice chairman of the party in January because of the party neutrality requirement.

He then vowed to seek the change so that future party leaders could support Trump in 2020.

Several Trump supporters in New Hampshire have encouraged Breton to pursue the change, which will require a two-thirds vote at the GOP’s annual meeting Jan. 26 at Pinkerton Academy in Derry.

Breton said he did not speak to Trump or his top political lieutenants about seeking this change.

But Sununu who just won his second term last month said it would be the wrong step to make.

“Whether it’s a primary for the New Hampshire House or the White House, the New Hampshire State Republican Committee must remain neutral in primaries,” Sununu said. “After hard-fought primaries, the state party is the vehicle to unite Republicans, and that is hard to accomplish if they try and tilt the scales for any candidate.”

Advisers to 2016 GOP candidate and outgoing Ohio Gov. John Kasich have condemned the proposal as threatening the integrity of New Hampshire’s first-in-the-nation presidential primary.

Former state Rep. Steve Stepanek of Amherst, the leading candidate to become the next GOP chairman, said he’ll stay neutral throughout the cycle if he gets named.

Trump said Thursday he wouldn’t discourage a primary challenge from Kasich or retiring Sen. Jeff Flake, R-Ariz., who also hasn’t ruled out a 2020 run.

“I hope so,” Trump told Fox News.

Hours later John Weaver, a Kasich adviser, responded to Politico, “Careful what you wish for.”

klandrigan@unionleader.com