WASHINGTON — CIA Director Bill Burns will meet in Ankara, Turkey, on Monday with his Russian intelligence counterpart to underscore the consequences if Russia were to deploy a nuclear weapon in Ukraine, according to a White House National Security Council official.

The official, who was not authorized to comment publicly and spoke on the condition of anonymity, said Burns and Sergei Naryshkin, the head of Russia’s SVR spy agency, would not discuss settlement of the war in Ukraine. Burns is expected to raise the cases of Phoenix Mercury star Brittney Griner and Michigan corporate security executive Paul Whelan, two Americans detained in Russia whom the Biden administration has been pressing to release in a prisoner exchange.

The Burns-Naryshkin meeting marks the highest-ranking face-to-face engagement between U.S. and Russian officials since before Russian President Vladimir Putin ordered the February invasion.

The official said that Ukrainian officials were briefed ahead of Burns’ travel to Turkey.

President Joe Biden, after meeting with China’s President Xi Jinping on the sidelines of the Group of 20 summit in Bali, Indonesia, told reporters that they discussed Russia’s war in Ukraine. Biden added they “reaffirmed our shared belief in the threat for the use of nuclear weapons is totally unacceptable.”

Kremlin spokesman Dmitry Peskov said Monday he could neither confirm nor deny reports of U.S.-Russia talks in Turkey.

Two Turkish officials said they had no knowledge about a meeting between U.S. and Russian delegations. A Turkish Foreign Ministry spokesperson could not immediately be reached for comment.

Biden, a Democrat, last month declared that the risk of nuclear “Armageddon” is at the highest level since the 1962 Cuban missile crisis, as Russian officials have raised using tactical nuclear weapons after suffering massive setbacks in the nearly nine-month invasion of Ukraine.

While U.S. officials for months have warned of the prospect that Russia could use weapons of mass destruction in Ukraine as it has faced strategic setbacks on the battlefield, Biden administration officials have repeatedly said nothing has changed in U.S. intelligence assessments to suggest that Putin has imminent plans to deploy nuclear weapons, according to U.S. officials.

The official added on Monday there has been no change in the U.S. intelligence assessment and declined to offer further detail on timing of the decision to send Burns to meet with Naryshkin.

Putin has repeatedly alluded to using his country’s vast nuclear arsenal, including in September as he announced plans to conscript Russian men to serve in Ukraine. Biden has sought to make clear that use of a lower-yield tactical weapons could quickly spiral out of control into global destruction.

Speaking at a conference of international foreign policy experts late last month, Putin said it’s pointless for Russia to strike Ukraine with nuclear weapons.

“We see no need for that,” Putin said. “There is no point in that, neither political, nor military.”

Biden sent Burns, a former U.S. ambassador to Russia, to Moscow last fall as the U.S. intelligence community saw signs that Putin was preparing to invade Ukraine.

The CIA chief’s travels are normally closely held, but the White House, as it did last year, has made the calculation that it’s best that Burns’ interaction with the Russian spy chief is widely known.