RIO DE JANEIRO, March 2 (Reuters) - Brazilian state-run oil company Petrobras has not taken a decision on fuel price adjustments, Chief Executive Joaquim Silva e Luna told Reuters on Wednesday.

He said that after Russia's invasion of Ukraine, the oil market was "nervous" and with many doubts.

"The world has plunged into a scenario of uncertainty," Luna told Reuters.

"That's what we're studying," he added when asked for how long Petrobras would support the rise in Brent prices, without making adjustments to the prices of oil derivatives on the domestic market.

This year's surge in oil prices was partially offset in Brazil by the devaluation of the dollar against the real. Exchange and Brent prices are the two main variables of the company's pricing policy, which is known as PPI.

The Petrobras CEO reiterated that the state-owned group that evaluates the price parity policy analyzes the scenario "minute by minute" before making any decision.

One of the hallmarks of Luna's management is not to pass on conjunctural movements in the oil market to domestic prices, and price adjustments are promoted through structural changes in the scenario. (Reporting by Rodrigo Viga Gaier; Writing by Peter Frontini; Editing by David Gregorio)