PARIS (Reuters) - France conducted a rare simulation of a nuclear deterrent mission, its armed forces ministry said on Tuesday, at a time when the United States plans to exit a nuclear arms control pact with Russia.

The 11-hour mission, which included refueling, tested all phases of an attack mission involving a Rafale warplane.

“These real strikes are scheduled in the life of the weapons’ system,” French air force spokesman Colonel Cyrille Duvivier said. “They are carried out at fairly regular intervals, but remain rare because the real missile, without its warhead, is fired.”

It did not say when the test was carried out, and officials declined to say how often they take place.

The mission comes as Paris looks to ensure its long-term nuclear dissuasion program, with Europe increasingly worried about security as tensions rise between Washington and Moscow.

Paris is also concerned over North Korea’s nuclear weapons program and Iran’s ballistic missile capabilities.

France spends about 3.5 billion euros ($4 billion) annually on maintaining its 300-strong submarine and air nuclear weapons stockpile. It plans to modernize its capacity to spend 5 billion euros a year by 2020.

It put an end to nuclear weapons testing in 1996 after a test in the South Pacific sparked global outrage and has since become a signatory of the Comprehensive Nuclear Test Ban Treaty.

The simulation comes after Russia suspended the Cold War-era Intermediate-range Nuclear Forces Treaty following the United States’ announcement it would withdraw from the pact, accusing Moscow of violations.

The 32-year-old treaty required parties to destroy ground-launched ballistic and cruise missiles with ranges of between 500 and 5,500 km (310 to 3,420 miles).

Paris urged Russia on Friday to use the six-month period triggered by the United States’ decision to comply with its obligations under the accord.

“We Europeans cannot remain spectators of our own security,” French Armed Forces Minister Florence Parly said on Tuesday at a conference in Portugal.