WASHINGTON (AP) - Committee chairmen expressed skepticism Tuesday that Congress can honor 2-year-old spending limits as Republican leaders began pitching an outline of a 2000 budget to the GOP rank-and-file.

"I can live with the caps," said House Appropriations Committee Chairman Bill Young, R-Fla., whose committee will start writing the bills in coming weeks. But, "can 218 members of the House live with caps?" he asked, referring to a majority of the 435-member chamber. "We'll see."

"I think we can stick to the caps if we have the votes to do so," Senate Appropriations Committee Chairman Ted Stevens, R-Alaska, said. "I'm not sure Congress can take the actions necessary to live within them."

Living within those spending limits, which were set in the 1997 budget-balancing deal, is among several principles GOP House and Senate leaders set last week as their guidelines for this year's budget fight with President Clinton. With narrow GOP congressional majorities and most Democrats favoring additional spending, the comments by Young and Stevens illustrated how tough it will be to keep Republicans united enough to obey the limits.

Even so, leaders said their plan would prevail.

"To start off this year saying, 'Oh, you know, we're going to just ignore these restraints we agreed to just two years ago,' is not good," Senate Majority Leader Trent Lott, R-Miss., said.

The spending bills account for nearly one-third of next year's expected $1.8 trillion budget. According to the budget agreement, they are limited to $536 billion next year. But there is pressure to spend perhaps $30 billion beyond that to boost defense and education and to keep programs even with inflation.

Besides honoring the spending limit, GOP leaders agreed last week to produce a budget with gradually growing tax cuts and reserving $1.8 trillion in projected Social Security surpluses over the next decade. The still unspecified tax cuts would be worth about $15 billion next year but swell to a 10-year cost of about $800 billion.

In closed-door sessions with House Republicans Tuesday afternoon, participants said House Speaker Dennis Hastert, R-Ill., told them of a morning meeting he had with Federal Reserve Chairman Alan Greenspan.

Hastert told Republicans that Greenspan "liked the idea of buying down the debt" and of providing tax cuts in future years, said one GOP leadership aide who spoke on condition of anonymity. "He was also very happy we held the line on spending," Hastert said, according to the aide.

Many House Republicans left a budget briefing from Hastert and House Budget Committee Chairman John Kasich, R-Ohio, with a positive attitude toward the budget framework.

"There was a sense in the room that we'd turned the corner, that we were back on our agenda," said conservative Rep. David McIntosh, R-Ind.

Meanwhile, Young said he was negotiating with administration officials over ways to pay for most of a $1.2 trillion emergency measure for Central American victims of Hurricane Mitch, aid to Jordan and help for U.S. farmers hurt by declining exports.

Clinton wanted to use this year's federal surplus to pay for most of the measure. But GOP leaders have insisted that savings be found instead. Young said his committee would vote on the bill today.

A $1.9 trillion version of the bill approved last week by Stevens' committee has drawn administration objections because it is paid for with cuts in money set aside for food stamps, welfare and other social programs.

"It doesn't sound very good, does it, cutting food stamps and needy families and immigration?" Stevens said.

But he said the money his committee was cutting wasn't going to be spent this year anyway and was preferable to paying for the bill with tax cuts or from budget surpluses.

The House and Senate budget committees will vote next week on the spending blueprints for fiscal 2000, which begins Oct. 1.