MOSCOW, OCT. 1 -- Tens of thousands of people across the Soviet Ukraine demonstrated today against control of the republic by the Communist Party and the Kremlin, while workers in some areas of the western Ukraine staged one-day strikes and called for total independence from Moscow.

In Kiev, the Ukrainian capital, crowds demonstrated outside the republic's legislature and demanded resignation of its current leadership. Many of the demonstrators carried placards declaring that a proposed new treaty to govern relations between Moscow and the 15 republics that make up the Soviet Union would undermine the sovereignty of the Ukraine. "The New Union Treaty Is the Old Slavery," one sign read.

With a population of more than 50 million, the Ukraine is the second largest Soviet republic after Russia and contains some of the most productive farming and industrial regions in the country. Thus, the Ukrainian independence movement is viewed in Moscow as a far greater threat to the cohesion of the Soviet state than that of the small Baltic republics, which were the first to demand independence.

The economic potential of the Ukraine is so great that Lenin, the founder of the Soviet state, once said: "To lose the Ukraine is to lose our head."

In such West Ukrainian cities as Lvov, Ternopol and Ivano-Frankovsk, the sentiment for total independence has grown especially strong in recent months. The long-banned Ukrainian Catholic Church has played a galvanizing political role there, much as the Catholic Church in Poland did with the Solidarity movement. In the Eastern Ukraine, where ethnic Russians form a high percentage of the population, political sentiment is mixed.

The demonstration outside the legislature provoked some havoc inside, including a heated debate over what flag the republic should use -- the red banner of its recent Soviet past or the blue-and-yellow emblem of old. The television news program Vremya showed legislators shouting at each other and battling for the microphone.

Demonstrators outside demanded that Ukrainians no longer serve in the Soviet army and that the Communist Party be declared a "criminal organization." The Ukrainian legislature already has declared the republic sovereign within the Soviet system, but lawmakers calling for radical change want it to follow the lead of the Baltics and Soviet Armenia, which have declared outright independence.

Vremya seemed to reflect Kremlin unease over the situation when the announcer observed that the call for strikes was effective only in some western regions. "It seems most people in the Ukraine realize there is no way for them to get out of our current crisis single-handedly," he said.