A committee of regional officials and private citizens took the initial step yesterday toward developing the first new master plan for transportation and growth in the Washington region since 1966.

But the 29-member panel brought together by the Metropolitan Washington Council of Governments attached a big if to its goal of drawing up a new plan by December. If the plan does not include recommendations on how it would be financed, some panel members said, the exercise will be pointless.

"There's one big shortcoming, and that's the money," said Montgomery County Council member Bruce T. Adams, the panel's co-chairman.

Estimates vary, but COG, the region's planning agency, said the area's shortage of transportation funding is $20 billion to $30 billion through the year 2010. In Northern Virginia alone, the shortage is $7 billion.

The panel is only advisory and has no authority to impose a plan on the region or to raise taxes. During the next five months, the panel wants to build a consensus by tackling some of the region's major transportation policy issues, such as whether to widen the Woodrow Wilson Bridge, the Capital Beltway and Interstate 66 and to complete the 103-mile Metrorail system.

In the last five years, as the region's congestion problem has become more acute, similar planning efforts have aimed at identifying the area's critical highway and transit needs. Each time a plan is suggested, however, it fizzles because politicians are afraid to ask voters to pay higher taxes to support the proposals.

"We're not short of plans at this point. We're short of money," said Fairfax County Supervisor Lilla Richards, the panel's other co-chairman.

But the group representing government and business in the District, Maryland and Virginia said it would consider including in its final report a financing plan even if that meant calling for higher taxes. Many of the panel's members are officials up for election or reelection this fall.

Adams said a call for higher taxes is likely to be unpopular given the region's property tax revolt and the anti-tax mood of business people.

"Neither the business community nor taxpayers are about to want to foot the bill for these extraordinary infrastructure costs," he said.

Money isn't the only obstacle. With 18 cities and counties, two states and five federal agencies involved, sharp differences are bound to surface over what transportation and growth policies to bless.

For example, Maryland officials adamantly oppose plans to build a western bypass through Montgomery County, while many Virginia officials support it.

Since 1966, regional planners have been using a master plan that called for highly developed growth corridors along major roads that radiated from the District to the suburban counties. Between the radial corridors were wedges of green space with less intense development.

But that plan has undergone several revisions, including the removal of several roads that planners now believe are needed to accommodate the region's growth. That's why the panel wants to develop what it called a "new vision" for the region.