The Senate’s No. 2 Republican on Tuesday spelled out GOP leaders’ conditions in the negotiations over reducing the federal deficit, offering the most specific outline of the party’s demands thus far.

Minority Whip Jon Kyl (Ariz.) told reporters that Republicans want $2.5 trillion in budget savings in exchange for voting to raise the country’s $14.3 trillion borrowing limit through the end of next year.

“You’d have to do about $2.4 trillion in debt ceiling,” Kyl said, “which means you’d have to be about $2 1/2 trillion — at a minimum — in savings.”

Ryan Patmintra, a spokesman for Kyl, clarified later Tuesday that $2.5 trillion was a reference to the figure used in a debt-limit measure rejected by the House last week, not to any number being discussed in the talks led by Vice President Biden.

House Speaker John A. Boehner (R-Ohio) said last month in an address to the Economic Club of New York that Republicans will not support any deal to raise the debt ceiling unless it is accompanied by spending cuts at least equal to the amount by which the borrowing limit is raised. But he has not given an exact figure, stating only that the cuts must figure in the “trillions, not billions.”

That has left the door open to an approach involving a series of votes to raise the debt limit, rather than a single vote ahead of the 2012 elections.

But Kyl’s remarks Tuesday were an indication that GOP leaders are looking to tackle the issue all at once, although he said a piecemeal approach remains a possibility.

“If we can’t get, in this case, about $2 1/2 trillion in real savings, then I don’t think there would be much of an appetite on our side to raise the debt ceiling by $2.4 trillion,” he said.

Kyl is one of six lawmakers participating in a working group led by Biden; its aim is to produce a comprehensive deficit-reduction plan in exchange for a vote to raise the debt ceiling, which the Treasury Department has said must be increased by Aug. 2 in order for the country to avoid default. The group’s fifth meeting is set for Thursday at the Capitol.

Biden said last month that the group was on track to identify at least $1 trillion in cuts, but there is a philosophical impasse between the parties: Democrats oppose any deal that would include cuts to entitlement programs such as Medicare, and Republicans have said they will not support any plan that includes tax increases.

The final steps toward a deal will probably be taken by the principals, including President Obama, Boehner and Senate Majority Leader Harry M. Reid (D-Nev.), as the deadline nears. A scheduled golf outing this month for Obama and Boehner could serve as the beginning of that process.