Russian lawmakers unanimously vote to de-ratify the nuclear test treaty. Here's what that means

Russian lawmakers unanimously voted Tuesday to revoke Russia's ratification of the Comprehensive Nuclear-Test-Ban Treaty, which bans any nuclear testing. 

While the motion requires two additional readings, Russia's lower parliament, the Duma, swiftly voted in favour of withdrawing Russia's ratification. The speaker of house, Vyacheslav Volodin, said lawmakers were taking this step in order to maintain "global strategic parity."

While Russia ratified the nuclear treaty in 2000, the United States and a number of other countries have signed on, but have never ratified it. 

What is the Comprehensive Nuclear-Test-Ban Treaty?

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) was adopted by the United Nations general assembly in 1996 in an effort to ban all nuclear explosions, including those underwater and underground. Its goal is to curb the development of nuclear weapons and also to eliminate the health and environmental risks that are caused by nuclear testing. 

Between 1945 and 1996 (which is when the treaty was tabled), there were more than 2,000 nuclear tests, most of which were conducted by the United States and the Soviet Union, according to the UN.

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Where the vast majority of countries have signed and ratified the CTBT, it is not in force because eight nations haven't ratified it, including China, the United States, North Korea, Israel, and Pakistan, which all have a nuclear weapons program. 

Since 1996, there have been 10 nuclear tests, according to the UN. Pakistan and India each conducted two tests, while North Korea has conducted six tests since 2006. Its most recent was in 2017. 

A verification system was developed alongside the treaty which led to the creation of an international monitoring program. There are 337 sites around the world which constantly monitor for signs of nuclear explosions.  

Why does Russia want to revoke its ratification and how significant is it?

Earlier this month, Russian President Vladimir Putin said Russia should withdraw its ratification to "mirror" the position of the United States, but that he wasn't not ready "to say whether we should conduct nuclear tests or not."

Russia has nearly 6,000 nuclear warheads — the largest stockpile in the world. 

Some experts see Russia's move as mostly symbolic as it doesn't appear to have immediate plans to resume nuclear testing. Nikolai Sotov, a Russian nuclear expert and senior fellow at the Vienna Centre for Disarmament and Non-Proliferation, says he believes the country is trying to make a political statement at a time of increasing hostilities with the West.

"This really illustrates (Russia's) tough approach," he said in an interview with CBC News. "Moscow used to be afraid of not having constructive negotiations, and now they are not afraid."

Russia has said it would remain a signatory to the CTBT, and continue to supply data to the global monitoring system. 

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Lynn Rusten, vice-president of the Global Nuclear Policy Program at the Washington, D.C.-based Nuclear Threat Initiative, says even if it is a political manoeuvre, it can still be viewed as an implicit threat by Russia. 

"You can also view it as another manifestation of Russia's kind of nuclear coercion in this Ukraine crisis," she told CBC News.

She says if Russia were to resume testing, it would put pressure on other countries to start testing nuclear weapons.

"The treaty's already under tremendous strain because the non-nuclear weapons states see that the nuclear weapon states … are going in the wrong direction in terms of starting to increase their nuclear arsenals."

Why has the U.S. not ratified it?

The U.S. signed the treaty in 1996, but the Senate voted against ratifying it in 1999.

At the time, U.S. officials expressed concern that the country might not be able to evaluate the reliability of its stockpile of weapons without the ability to occasionally do nuclear tests. Another concern was whether there was a strong enough system in place to ensure countries adhered to the treaty.

Rusten says those concerns have now mostly vanished because of the monitoring systems now in place, but she says there hasn't been a strong desire to ratify it in the U.S. 

"There's kind of an ideological antipathy toward arms control in some quarters," she said. 

Even though the U.S. hasn't ratified it, she says it has been committed to the moratorium on any nuclear testing. 

What is the status of global nuclear disarmament?

Throughout Russia's war on Ukraine, Putin and other Russian officials have made nuclear threats.

Earlier this year, Russia announced it was suspending the New Start Treaty with the U.S., which is the last remaining arms treaty between the two countries. It limits the number of strategic nuclear warheads on both sides. 

Of the 12,500 nuclear warheads in existence, nearly 90 per cent belong to the United States and to Russia, according to the Federation of American Scientists. In March, Russia announced it was deploying tactical nuclear weapons to Belarus

Putin said he saw no need to change the doctrine, which states that Russia may use nuclear weapons in response to a nuclear attack or an attack with "weapons of mass destruction." It also states that Russia can deploy nuclear weapons if its existence is threatened by conventional weapons. 

Sotov, who took part in arms control negotiations in Russia between 1987 and 1992, said he doesn't think Russia will resort to using nuclear weapons on the battlefield in Ukraine, but believes Russia could target a NATO country.

"If the war really goes bad for Russia, it will try to escalate conventional conflict with NATO," he said. "But when you are locked in escalation, it spirals and you may unintentionally actually go nuclear."

Foreign correspondent

Briar Stewart is CBC's Russia correspondent, currently based in London. During her nearly two decades with CBC, she has reported across Canada and internationally. She can be reached at briar.stewart@cbc.ca or on X @briarstewart

-- with files from Reuters