UPDATE 1-Brazil's Petrobras says no hit to production, safety from workers' strike

(Adds details of court ruling, details on the extent of the strike, adds RIO DE JANEIRO to dateline)

SAO PAULO/RIO DE JANEIRO, Feb 4 (Reuters) - A four-day-old strike by workers at Brazil’s Petroleo Brasileiro SA, or Petrobras, has not yet affected production or jeopardized safety across the company’s operations, the state-owned oil company told Reuters on Tuesday.

“There has been no impact on production or supply to the market,” Petrobras said in a statement sent to Reuters.

“The company notes that all of its oil, fuel and derivatives production units are operating within safety standards,” the company added.

Ives Gandra Martins Filho, a federal labor judge, said on Tuesday that the striking workers must not prevent the free movement of goods and people at Petrobras plants or those of its subsidiaries.

According to Martins Filho, 90% of Petrobras employees are working and carrying out their duties as normal.

Meanwhile, the Federação Única dos Petroleiros group of unions, or FUP, said in a statement that around 14,750 workers are now on strike, or 80% of the total in the 12 states where the industrial action is taking place.

Unions say the strike, which began on Saturday, is in protest of layoffs at a loss-making fertilizer factory in the state of Paraná closed by Petrobras, and they also accuse the company of failing to comply with a collective labor agreement known as ACT.

But Petrobras claims the strike is unjustified, as the collective bargaining agreement was signed by all unions in November last year and negotiations are ongoing.

One of the FUP-affiliated unions, Sindipetro Norte Fluminense, said in a statement on Tuesday it instructed workers to walk off platforms and hand them over to management, which could potentially impact production.

On Monday, Petrobras said it was calling in contingency teams to maintain operations, and even taking legal action in some cases to avoid any disruption to operations. (Reporting by Luciano Costa in Sao Paulo and Marta Nogueira in Rio de Janeiro Writing by Jamie McGeever in Brasilia Editing by Louise Heavens and Matthew Lewis)