The Virginia attorney general's office warned today that the state's conflict-of-interest law strictly forbids legislators to vote on any issue in which they have a personal financial interest, a finding that legislators said could bring General Assembly business to a halt.

Deputy Attorney General Francis Lee stunned a House committee with his interpretation of a 1984 decision by the Virginia Supreme Court that he said would significantly alter members' voting practices. Lee said the ruling means, for example, that lawyers must abstain on matters affecting law practices and legislators who sit on bank boards must not vote on banking matters.

"That language is so broad we could not even adopt a budget. It affects every officeholder," said House Speaker A.L. Philpott (D-Bassett). "We would be eunuchs."

Lee appeared before the House Privileges and Elections Committee after turmoil in several major committees over the past week, where actions that were previously considered routine were postponed because of legislators' nervousness. In recent days, record numbers of members have abstained from voting on bills because of fears of conflict charges.

The legislature already has been jolted this year by the criminal prosecution of the Senate's fourth-ranking member, Sen. Peter K. Babalas (D-Norfolk), who faces conflict-of-interest charges. The Babalas charges focus on his vote to kill a bill that would have imposed tighter restrictions on second-mortgage companies, one of which paid him $61,000 in legal fees.

The chairman of the Senate Commerce and Labor Committee, where two-thirds of the members have substantial financial ties with the banking industry, today postponed action on the controversial issue of limiting credit-card interest rates, saying he would ask the Senate Rules Committee to review the question of potential conflicts. That committee is expected to debate the issue Tuesday.

"This body is extremely sensitive at this point concerning this issue," said Sen. William E. Fears (D-Accomac), committee chairman and a bank director.

The companion House Corporations, Insurance and Banking Committee, with three-fourths of its membership involved with financial institutions, asked last week for a similar ruling.

Lee's strict interpretation of the conflict law stems from the state Supreme Court's November 1984 ruling that the mayor of Richmond, who also serves as a member of the City Council, could not vote on the selection of a new school superintendent because the mayor also was employed as a city school principal.

Early in the session, Philpott and others drafted a law they believed would restore to legislators most of the voting authority that the court ruling had voided. But after Lee's comments today, lawmakers said the decision was much farther-reaching than they originally believed and noted that the proposed law will need drastic alterations.

Some lawmakers said the General Assembly could face gridlock if it doesn't rewrite the law that prompted what they labeled an overly broad ruling by the state Supreme Court.

"We know we've got a severe problem with the law," said Del. Theodore V. Morrison Jr. (D-Newport News).

"I don't see it as a way of weakening the law. We're trying to have a workable law," said Del. Ford C. Quillen (D-Gate City), chairman of the committee that is working to change the law.

"As long as you have a citizen legislature . . . the fact that you have some type of private sector job shouldn't preclude you from voting."

The Virginia Supreme Court issued its opinion on the conflict-of-interest statute more than a month before last year's General Assembly convened, but legislators said they didn't become concerned with its impact until the Babalas case.

Until the Supreme Court ruling, legislators generally considered it acceptable to vote on measures that affected an industry in general, but said that members should abstain when their business, family or clients would be affected directly.

The state's conflict-of-interest law was passed in 1970 but did not include the legislature.

In 1983, after several embarrassing public scandals over conflicts of interest of General Assembly members, the legislature voted to include itself under the act.