WASHINGTON • The US military intelligence agency has stepped up its accusations against Russia over low-yield nuclear testing, saying that the country has conducted nuclear weapons tests that resulted in nuclear yield.
A new statement from the Defence Intelligence Agency (DIA) amounted to a more direct accusation against Russia, compared to hedged comments about Russian nuclear testing that agency director Lieutenant-General Robert Ashley Jr made in a speech in Washington last month.
"The US government, including the Intelligence Community, has assessed that Russia has conducted nuclear weapons tests that have created nuclear yield," the DIA statement released on Thursday said. The agency did not give any details about the alleged tests or release any evidence backing up the accusation.
The US Intelligence Community is a federation of 17 government agencies that work separately and together to conduct intelligence activities in support of the country's foreign policy and national security.
Previously, the agency's director said that Russia probably was not adhering to the zero-yield standard the United States applies for nuclear testing. He suggested that Russia was probably conducting tests with explosions above a subcritical yield as part of its development of a suite of more sophisticated nuclear weapons.
Moscow has vehemently rejected Washington's accusations, with Russian Foreign Minister Sergei Lavrov describing them as delusional.
"We consider claims that Russia may be conducting very low-yield nuclear tests as a crude provocation," Russia's Foreign Ministry said in a statement after the DIA first aired the allegations. "This accusation is absolutely groundless and is no more than another attempt to smear Russia's image."
The DIA's latest accusation came a day after Under Secretary of State for Arms Control and International Security Andrea Thompson met Russian Deputy Foreign Minister Sergei Ryabkov in Prague to discuss arms control.
The meeting did not result in any significant decisions. After the meeting, Ms Thompson said in a message on Twitter that she raised a range of issues on which the US would like to engage in a more constructive dialogue with Russia.
During the meeting, Mr Ryabkov said he reiterated the unacceptability of Washington's accusations regarding alleged Russian nuclear testing and the Comprehensive Nuclear Test Ban Treaty, a 1996 agreement that prohibits nuclear explosions.
"We said that we are in full and absolute compliance with the agreement, ratified by Moscow, and in full compliance with our unilateral moratorium on nuclear testing," Mr Ryabkov said, according to the Russian state news agency RIA Novosti.
The DIA's original accusations in late May came after the Wall Street Journal reported that a new US intelligence assessment found Russia likely has tested nuclear weapons with very low yields at Novaya Zemlya, a collection of islands in the Arctic Circle.
In addition to provoking a rebuke from Russia, the US government's accusations about Russian low-yield testing have prompted scepticism among some disarmament advocates.
The James Martin Centre for Nonproliferation Studies in Monterey, California, said its regular open-source monitoring of Novaya Zemlya had not detected any alarming activity.
In a statement late last month, the centre's Eurasia programme director Sarah Bidgood said that with no new evidence that Russia is conducting low-yield tests, it appears that US officials are rehashing past allegations about Russian test violations "in order to support the narrative that Russia is an unreliable partner in arms control, with whom verification does not work".