PROVIDENCE, R.I. – In an extraordinary move, Donald Trump’s Republican rivals late Sunday announced plans to coordinate primary strategies in upcoming states to deprive the GOP front-runner of the delegates needed to win the Republican nomination.

Ted Cruz and John Kasich issued near-simultaneous statements outlining an agreement that may be unprecedented in modern American politics. The Kasich campaign will give Cruz “a clear path in Indiana.” In return, the Cruz campaign will “clear the path” for Kasich in Oregon and New Mexico.

The arrangement does not address the five Northeastern states set to vote Tuesday, where Trump is expected to add to his already overwhelming delegate lead. Kasich and Cruz had already retreated to Indiana, which holds its primary on May 3. Yet the shift offers increasingly desperate Trump foes a glimmer of hope in their long and frustrating fight to halt the former reality television star’s unlikely rise.

“Having Donald Trump at the top of the ticket in November would be a sure disaster for Republicans,” Cruz’s campaign manager, Jeff Roe, said in a statement explaining the new plans. “Not only would Trump get blown out by Clinton or Sanders, but having him as our nominee would set the party back a generation.”

Added Kasich’s chief strategist, John Weaver, “Our goal is to have an open convention in Cleveland, where we are confident a candidate capable of uniting the party and winning in November will emerge as the nominee.”

The announcement marks a sharp reversal for Cruz’s team, which aggressively opposed coordinating anti-Trump efforts with Kasich as recently as late last week. And it only applies to Indiana, Oregon and New Mexico – three of the 15 states remaining on the Republican primary calendar.

Trump responded on Twitter shortly before midnight: “Wow, just announced that Lyin’ Ted and Kasich are going to collude in order to keep me from getting the Republican nomination. DESPERATION!”

The announcement came less than 48 hours before voting begins across five Northeastern states where the New York billionaire leads in many polls. Trump campaigned Sunday in Maryland, which will vote on Tuesday along with Rhode Island, Connecticut, Pennsylvania and Delaware.

As Kasich backs out of Indiana, Cruz promised to not compete in primary contests in Oregon on May 17 and New Mexico on June 7.

“We will focus our time and resources in New Mexico and Oregon, both areas that are structurally similar to the Northeast politically, where Gov. Kasich is performing well,” Weaver said.

There was far less drama on the Democratic side Sunday.

Underdog Bernie Sanders rallied thousands of voters in two New England states, seeking momentum even as he offered mixed signals on how hard he would push his differences with front-runner Hillary Clinton.

The Vermont senator largely steered clear of Clinton at a Rhode Island park, but hours later ramped up his critique before more than 14,000 supporters in New Haven, Connecticut. Sanders reiterated his call for Clinton to release transcripts of lucrative Wall Street speeches she delivered after leaving the State Department in early 2013.

Clinton eyed victories in four or five of Tuesday’s contests, which would all but cripple Sanders’ White House bid.

The former secretary of state went to two Philadelphia church services ahead of the primary in Pennsylvania, Tuesday’s top delegate prize. She declined to attack her Democratic rival by name in the morning appearance and a subsequent stop in Bridgeport, Connecticut, focusing on the GOP candidates.