A top Ukrainian official says the country will select military targets on Russian territory as a means of defense, pointing to what he says is approval from U.S. Secretary of State Antony Blinken.

Mykhailo Podolyak, adviser to President Volodymr Zelenskyy, posted the declaration to Twitter on Thursday.

“Ukraine must decide for itself whether to strike at Russian military facilities, said @SecBlinken. Russia has attacked Ukraine and killed civilians. Ukraine will defend itself in any way, including strikes on the warehouses and bases of the killers. The world recognizes this right,” Podolyak wrote.

The post was an apparent reference to a statement made by Blinken during his testimony before the U.S. Senate’s appropriations subcommittee.

“It’s another matter as to whether Ukrainians should take actions that go beyond their borders. My own view is that it’s vital that they do whatever is necessary to defend against Russian aggression and the tactics of this are their decision,” Blinken said.

Nikolai Patrushev, secretary of the Security Council of the Russian Federation, subsequently stated the need for creation of a system that warns Russian citizens of potential air raids and that bomb shelters to be brought “in proper condition,” according to the Russian news agency ITAR-Tass.

Patrushev singled out Russia’s western regions as primary targets and noted the high risk of attack using chemical and biological weapons. Ukraine has never used chemical or biological weapons, and independent sources have refuted the Russian claim the Ukrainians have developed the weapons.

Throughout April, Russia has reported multiple explosions on its territories, accusing Ukraine of each one.

One of the latest attacks, on April 27, the governor of the western Russian region of Belgorod, Vyacheslav Gladkov, reported explosions, something he said sounded like anti-aircraft defense systems.

He later reported that it was an ammunition storage facility. On the same day, the governor of the Kursk Oblast region, Roman Starovoyt, said that the region’s citizens reported similar explosions.

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