Any resolution to the shutdown standoff now gripping Capitol Hill will have to involve senators from both parties locking arms. It would probably help if the two top party leaders in the Senate would start talking to each other first.

Instead, a frosty pall has settled over the working relationship between Majority Leader John Thune and Minority Leader Chuck Schumer, with the two Senate veterans bickering over the path forward for a shutdown-averting stopgap bill.

As of Tuesday evening, neither man had spoken to the other on the subject, with each saying the other bears the burden of actually starting any conversation.

The stalemate between the two, who have served in the chamber together chummily for decades, encapsulates the partisan tensions that have raised the odds that Congress will fail to act and government agencies will close at midnight Tuesday.

Schumer in recent days attempted an end run around Thune, going directly to President Donald Trump with House Minority Leader Hakeem Jeffries to demand a meeting. After the White House moved to arrange that meeting, Thune and Speaker Mike Johnson relayed their concerns to Trump, who then canceled it.

It’s just the latest instance of the two leaders, who are each balancing larger political pressures, not being on the same page since January. But now, with the stakes as high as they’ve been all year, some senators are hinting it’s time for a thaw.

Sen. Tim Kaine (D-Va.) said he believed Schumer and Thune could “figure this out” if only they could figure out how to get a conversation started.

“When people have offices very near each other and know each other’s phone numbers, I don’t think they should, ‘You gotta call me’ — ‘No, I gotta call you,’” he said. “Both need to be talking.”

But so far Schumer and Thune appear dug in. Schumer’s view is that Thune needs Democratic votes and thus should be reaching out. Thune’s view is that there is nothing to negotiate at the moment given that Republicans are offering a “clean” seven-week funding extension similar to ones Democrats have supported in the past.

It’s not clear what would come of any conversations, with senators skeptical that either leader will readily move from their current positions. While the New York Democrat is demanding a “bipartisan negotiation” centering on health care — primarily soon-to-expire health insurance subsidies — the South Dakota Republican sees no reason to cut a deal now on something that won’t go into effect until the end of the year.

Thune accused Schumer of trying to take funding “hostage” to satisfy his base, while Schumer said Thune is blindly following Trump’s lead as the president appears stuck in “go-to-hell mode.”

“I don’t think they’ve been sharing hugs,” Sen. John Kennedy (R-La.) said about the two leaders.

The chilly relationship is a rather new development. Schumer and Thune have served together in the Senate for more than 20 years, including overlapping on the powerful Finance Committee. Even into the first Trump administration, Thune spoke about his regular run-ins with Schumer in the Senate gym.

Late last year, as Thune prepared to take over from Sen. Mitch McConnell (R-Ky.) as top GOP leader, Schumer took to the floor to congratulate him, saying that “we’ve done many bipartisan things here in the Senate together.”

But since Thune officially moved into the job in January, the two haven’t had a regularly scheduled meeting — unlike Thune and Johnson. And unlike McConnell, Thune hasn’t yet needed to lock arms with Schumer to deliver significant legislation — something the Kentucky Republican did on a debt ceiling hike, Ukraine aid and multiple rounds of federal help during the coronavirus pandemic.

Their biggest test, in fact, could be what comes after Oct. 1 — whether that’s finding their way out of a shutdown or notching the sweeping end-of-year funding deal envisioned by appropriators.

Thune said in a recent interview that, while he sits down with Schumer “occasionally” or they chat on the floor, their talks are “spontaneous” or driven by the “need of the minute.”

Their perfunctory working relationship has been on full display for their colleagues recently. They didn’t speak during a recent negotiation to tee up competing Republican and Democratic stopgap bills for a vote last Friday. They instead let top staffers, who have a good relationship and talk with each other almost constantly about routine Senate business, sort it out.

Thune has ceded most of the day-to-day talks over the larger government funding bills to Appropriations Chair Susan Collins (R-Maine), who is still optimistic about being able to strike a deal with the House on three full-year bills. But when asked about a shutdown-avoiding stopgap, she pointed back to Thune and Schumer: “I think that has gone to the leadership level.”

Thune and Schumer did speak on the Senate floor during unsuccessful negotiations around rules changes for nominations earlier this month. But Thune later joked that Schumer “couldn’t get out of that meeting fast enough.”

Both leaders’ political calculations are playing into the pas de deux. Schumer is under fierce pressure from the Democratic base to counter Trump and Republicans after caving under similar circumstances in March. (He and Thune did speak in the lead-up to that widely criticized vote.)

The New Yorker is now insisting Republicans will bear the brunt of the political fallout following a shutdown since they control both chambers of Congress and the White House. Speaking to reporters after the Senate voted down two dueling funding bills last week, Schumer said Republicans will “absolutely” be blamed, adding that “the world is totally changed from March.”

Thune, meanwhile, has to navigate Trump’s unpredictable machinations. Back in July, Thune, Schumer and their deputies sought to negotiate an agreement that would have expedited the confirmations of some administration nominees in return for the release of frozen agency funding. A deal was close, but Trump wouldn’t get on board, telling senators to go home instead — handing Schumer the opportunity to declare a small victory.

That unpredictability was underscored again by the White House meeting that was scheduled and then unscheduled at GOP leaders’ behest Tuesday. Thune also has to factor in that Trump has yet to sketch out a position on Democrats’ baseline demand: extending the health insurance subsidies that expire on Dec. 31.

The South Dakotan has been careful not to get ahead of Trump this year on legislation, knowing that if the president stakes out a different position it could put him, and his GOP members, in a politically awkward spot. Furthermore, he sees no reason to address a deadline that is still months away.

“Eventually, ultimately, the White House and Schumer are going to have to probably sit down,” Thune said in a brief interview earlier this month. “But I think right now what we’re talking about is short-term.”

Katherine Tully-McManus contributed to this report.