An influential business group in Northern Virginia issued a blunt warning to the region's legislative candidates today about the possible need for higher transportation taxes, admonishing the politicians against signing a "taxpayer protection pledge" that several of them already had signed.

In a two-hour, closed-door session at George Mason University, about 40 members of the Northern Virginia Roundtable made it clear that they will not tolerate--or give money to--local incumbents and challengers who sign an anti-tax pledge being circulated nationally by the Washington-based Americans for Tax Reform.

In January, as the General Assembly session started, all 33 delegates and senators from the Washington suburbs signed a letter that held open the door to higher taxes as one option in solving the region's transportation crisis.

"We will take note of those who do not honor that commitment," said James W. Dyke Jr., the new president of the Fairfax County Chamber of Commerce and one of four participants who described the meeting.

"That point was made very clear this morning," Dyke said. "We're going to keep score."

The morning session was the latest in a series of events punctuating an increasingly intense statewide debate about how to pay for roads, as regions fight regions for resources and Gov. James S. Gilmore III (R) angers groups like the roundtable that want him at least to think about higher taxes.

Seven Republicans in the legislative delegation signed the pledge, which nationally has the backing of 1,128 other lawmakers, as well as Gilmore's. No Democrat in the delegation signed the pledge.

According to the tax reform group, the pledge commits a legislator to oppose any effort raising taxes on individuals and corporations, even in the event of a fiscal crisis or natural disaster.

When told about what the business people said this morning, Grover Norquist, the head of the reform group, said: "Idiots! . . . They're not applying their own common sense to government."

Norquist, a member of a national electronic commerce commission headed by Gilmore, said the main point of the pledge is that politicians should "opt for the less-government position rather than the more-government position."

The pledge does contain a kind of safety valve, allowing taxes of one type to go up if another type goes down to compensate, an idea that Norquist dismissed as "usually worthless."

This morning, when Del. Vincent F. Callahan Jr. (R-Fairfax) defended his signing by explaining that escape hatch, roundtable members started chuckling, while other audience members rolled their eyes and groaned, according to interviews with some of those in attendance.

Callahan said later that his tax-cutting record is second to none, adding that he helped usher in the 1990s era of tax cuts in Virginia, capped by Gilmore's signature car-tax repeal.

Even if transportation taxes rise, "the net effect is that he still would be a cutting-tax governor," Callahan said. But, parting company with Gilmore, who adamantly opposes any tax increase, Callahan added that "everything should be on the table" in highway financing.

Leslie L. Byrne, a former Democratic state delegate and former member of Congress now running for state Senate, said the business group delivered a simple message to the lawmakers: "Keep your options open, don't make any promises you can't keep."

The six GOP delegates who took the pledge were David B. Albo (Fairfax); Callahan; Jay Katzen (Fauquier); Robert G. Marshall (Prince William); Roger J. McClure (Fairfax); and James K. "Jay" O'Brien Jr. (Fairfax).

The lone senator who signed was Jane H. Woods (R-Fairfax), Byrne's opponent in the Nov. 2 election.