The strikers had picketed the plant almost every day, except for weekends. Early on Monday, at least 500 people had gathered outside the building.
"Local authorities have banned pickets," Alexei Etmanov said.
Although production has been partially resumed at the sole Ford factory in Russia, the plant is still failing to reach target output levels.
"The administration has launched a night shift, but this produced only 38 of the 100 cars requested per shift" Etmanov said, adding that the total number of workers involved in the strike had not changed.
An official spokesman for the company refused to comment on the situation.
Around 1,000 workers at the factory halted production on November 20, demanding a 30% pay rise. Some 600-700 workers later crossed the picket line on November 28, and production was partially resumed.
There are presently around 650 workers on strike. The factory employs some 2,000 people.
The ongoing Ford strike has been heralded by many Russian social observers as the birth of organized union activity in post-Soviet Russia.
Unions in the U.S.S.R were mainly concerned with productivity, morale and the organization of workers' annual holidays. After the collapse of the Soviet Union, the role of trade unions in society became somewhat vague, and the Ford pickets represent the strongest union action in Russia for many years.
Boris Kravchenko, president of the All-Russian Confederation of Labor, has said the workers are not civic heroes, but simply "fighting to improve their work conditions."
