Efforts to revamp the regulatory process could be derailed if Congress adopts a governmentwide legislative veto proposal currently under consideration, the Carter administration warned yesterday.

In addition, the administration said in tersely worded letters to members of the House Judiciary Committee that proposals submitted to Congress by the Business Roundtable to revise rulemaking standards "will undercut the overall aim" of regulatory reform legislation.

The letters, signed by Stuart Eizenstat, President Carter's top domestic affairs aide, and James McIntyre, director of the office of Management and budget, were sent to Judiciary Committee members as they prepared to finish action on a regulatory reform package.

Although the administration had been pushing actively for regulatory reform legislation, recent action by the Senate Judiciary and Governmental Affairs committees and possible action by the House panel are threatening to reverse the view of administration officials, sources said yesterday.

The Senate Government Affairs Committee last week passed a provision that would allow both houses, with presidential approval, to veto major government rules, and the House committee this week will consider similar legislation.

A House Judiciary subcommittee has rejected such a proposal, but in the letter Eizenstat and McIntyre warned that that the administration "cannot approve any such measure."

"To enforce governmentwide legislative veto, Congress will either have to expand radically its own staff bureaucracy, or else become responsible for thousands of minutely detailed regulatory decisions without adequate capacity to monitor or evaluate them," the officials wrote.

Secondly, the administration officials warned against congressional approval of a measure already passed by the Senate Juciciary Committee that would give federal courts wider latitude to monitor federal regulations. That amendment to the regulatory reform bill was submitted by the Business Roundtable on May 1, Eizenstat and McIntyre said.

"This measure will undercut the overall rim of the regulatory reform bill . . ." they wrote. "The amendment will also impair the ability not only of the president, but of Congress to assure that regulatory decisionmakers are accountable and faithful to statutory mandates."

The officials went on to warn the committee to "resist any additional last-minute recommendations by particular private groups that will serve to complicate regulatory procedures."

The two Senate committees are trying to reconsile the significant difference in the two bills.

The House Judiciary Committee also is considering a regulatory reform package, with many of the proposals already endorsed by the Carter administration.