Earlier in the day, the Sky News broadcaster reported that the United Kingdom might deploy drones in the Persian Gulf to boost surveillance and help protect UK-flagged ships amid recent tensions with Iran.
"Our region will not be safe if military presence there expands. Boosting military contingent in the Persian Gulf will lead to insecurity in the region," Zarif said in Moscow.
The foreign minister stressed that security in the Persian Gulf could not be ensured without Iran's engagement.
Tensions spiked after Gibraltar detained an Iranian oil tanker Grace 1 on July 4 on suspicion of violating EU sanctions against Syria. Two weeks later, a UK-flagged tanker Stena Impero was detained by Tehran.
Grace 1, later renamed Adrian Darya, was released in August. Meanwhile, the owner of Stena Impero met with Zarif to make the case for the ship to be released.