BELGRADE, AUG. 11 -- Bulgaria's ruling Communist Party will be stripped of much of its authority and pomp and be opened to opposition from other organizations under plans outlined by veteran leader Todor Zhivkov, the official Bulgarian news agency reported today.

The agency, BTA, monitored in this Yugoslav capital, gave more details of last month's party plenum, where Zhivkov called for a radical shake-up of the political system.

BTA said the plenum decided the party could no longer be "a rung in the hierarchy of authority" and that it would eliminate pomp and ceremony from the political arena. Instead, authority should be wielded by self-managing organizations set up under Bulgaria's economic reform program, which is being extended into the country's political system, the plenum reportedly concluded.

The party would determine general development guidelines but self-governing bodies would have the right to apply these guidelines according to their own conditions, BTA said. The supreme authority would then rest in a reshaped National Assembly.

"Apart from partners, the party and state bodies can also be opponents when necessary," the agency said, quoting the plenum document.

The document also attacked "falseness, ostentation and formalism" in the party, urging the removal of displays of portraits of party leaders, parades and other "superfluous pomposity, megalomania and needless advance orchestration." It advocated a transition from "power in the name of the people" to "power exercised through the people," and added that new rules would be formulated to govern the behavior of top officials.

Zhivkov has ruled Bulgaria for more than 30 years and has emerged as a champion of reform since Soviet leader Mikhail Gorbachev came to power in Moscow.