Ukraine and its allies have adamantly rejected Russia's claims that Kyiv is developing a "dirty bomb" to use against Moscow's forces, and Ukraine's foreign minister says he has invited experts to visit Ukrainian facilities to see for themselves that Ukraine has nothing to hide.
Russia's claims that Kyiv is planning to deploy a so-called dirty bomb -- a conventional warhead laced with radioactive, biological, or chemical materials -- came in a series of calls between Russian Defense Minister Sergei Shoigu and his counterparts from several NATO countries.
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Britain, France, and the United States issued a joint statement on October 23 dismissing the claim after Shoigu's calls with their defense ministers in which the Russian minister presented no evidence for the claim.
"Our countries made clear that we all reject Russia's transparently false allegations that Ukraine is preparing to use a dirty bomb on its own territory," according to the statement.
But Russia doubled down on its assertions, which come after weeks of military defeats for Russia in southern and eastern Ukraine.
"According to the information we have, two organizations in Ukraine have specific instructions to create a so-called dirty bomb. This work is in its final stage," Lieutenant General Igor Kirillov said on October 24.
Later the same day, the chief of the Russian General Staff, Valery Gerasimov, spoke by phone with British Chief of Defense Staff Tony Radakin, who rejected Russia's allegations that Ukraine is planning actions to escalate the conflict.
"The military leaders both agreed on the importance of maintaining open channels of communication between the U.K. and Russia to manage the risk of miscalculation and to facilitate de-escalation," the Defense Ministry said in a statement.
SEE ALSO: Eight Months Since The InvasionGerasimov also held a phone call with his U.S. counterpart, General Mark Milley, to discuss the risks of the use of a dirty bomb in Ukraine, according to the Kremlin-controlled RIA Novosti news agency.
NATO Secretary-General Jens Stoltenberg weighed in on Moscow's repeated allegation on October 24 , saying NATO also rejects it.
Stoltenberg said he had spoken with U.S. Defense Secretary Lloyd Austin and British Defense Secretary Ben Wallace "about Russia's false claim that Ukraine is preparing to use a dirty bomb on its own territory."
"NATO Allies reject this allegation. Russia must not use it as a pretext for escalation. We remain steadfast in our support for Ukraine," he said on Twitter.
Moscow's claims that Ukraine could employ a dirty bomb raised concern that Russia could use such a device and blame Kyiv.
A senior U.S. military official said the United States has seen no indication that Russia has decided to use nuclear, chemical, or biological weapons in Ukraine, including a dirty bomb.
The official, who spoke to journalists on condition of anonymity, also said the Ukrainians are not building a dirty bomb.
U.S. State Department spokesperson Ned Price also said the United States has not seen any indication that Russia is preparing to use a nuclear weapon but said there would be consequences for Russia whether it used a dirty bomb or any other nuclear weapon.
"It would certainly be another example of [Russian] President [Vladimir] Putin's brutality, if he were to use a so called 'dirty bomb.' There would be consequences for Russia whether it uses a 'dirty bomb' or a nuclear bomb. We've been very clear about that," Price told reporters.
He did not provide details about those consequences.
Ukraine earlier called the accusation that Kyiv was building a dirty bomb absurd, and Foreign Minister Dmytro Kuleba said the head of the UN's nuclear watchdog accepted his request to send experts to Ukraine to refute Moscow's claim.
Kuleba said he invited the International Atomic Energy Agency (IAEA) to "urgently send experts to peaceful facilities in Ukraine which Russia deceitfully claims to be developing a dirty bomb."
Kuleba said Ukraine has always been transparent and has "nothing to hide."
The IAEA said later on October 24 that it was preparing to send inspectors to two Ukrainian sites.
IAEA chief Rafael Grossi confirmed in a statement that both locations are under IAEA safeguards and have been visited regularly by the agency's inspectors.
The IAEA "is aware of statements made by the Russian Federation on [October 23] about alleged activities at two nuclear locations in Ukraine," Grossi said, adding that both were already subject to its inspections and one was inspected a month ago and no undeclared nuclear activities or material were found.
"The IAEA is preparing to visit the locations in the coming days," it added.
U.S. Secretary of State Antony Blinken told Kuleba in a phone call on October 23 that the world would "see through any attempt by Russia to use this allegation as a pretext for escalation [of the war]."
Blinken and Kuleba discussed the U.S. and international commitment to continue supporting Ukraine with "unprecedented security, economic and humanitarian assistance for as long as it takes, as we hold Russia accountable," the State Department's call readout said.
They further noted ongoing efforts to manage the broader implications of the Kremlin’s war in Ukraine, it added.