Putin faced questions from the public during his annual call-in show in Moscow - Pool Sputnik Kremlin

Vladimir Putin has accused the United States of violating the nuclear balance and warned against a “Third World War” during an annual televised call-in show.

Responding to a worried viewer, Mr Putin called for new arms control negotiations and quoted Albert Einstein's aphorism that “World War IV will be fought with sticks and stones”.

But he also said Russia had developed weapons to overcome US missile defence after Washington left the Soviet-era anti-ballistic missile treaty in 2002.

“The fear of mutually assured destruction has always restrained and forced military powers to respect each other,” he said. “The exit of the United States from the missile defence treaty was an attempt to ruin this parity, but our efforts in the development of new weapons will preserve this parity.”

These “invincible” nuclear weapons, which include an underwater drone and hypersonic glider warhead, sparked fears of a new arms race when the Russian leader first announced them in March.

Russian Iskander missile on the carrier rolls during the Victory Day Red Square Military Parade in Moscow Credit: Mikhail Svetlov/Getty

US intelligence has claimed Moscow's nuclear-powered hypersonic cruise missile with “unlimited” range crashed in tests.

But Mr Putin argued that Russia had already proved doubters wrong by successfully developing weapons like the Avant-Garde missile, which flies 20 times faster than the speed of sound. The Mach-10 Dagger missile and a laser weapon are already in service, he said.

The Cold War rhetoric continued as Mr Putin likened Western sanctions on Russia to the US containment policy against the USSR.

He also cited Soviet successes in the space race while pledging to launch 600 new satellites and develop a super-heavy rocket.

During the four-and-a-half-hour show, Mr Putin answered 73 questions out of more than 2 million submitted by the country's residents.

Vladimir Putin takes questions during the show, many of which were recorded on the scene by state television crews Credit: Mikhail Klimentyev/TASS via Getty Images

The event is carefully stage-managed, although a few uncomfortable questions popped up on screens showing submissions in real time.

“Why is there money for tanks, bombs, planes and machine guns in this country, but not for people?” read one, but the presenters ignored it.

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Among the “never-ending accusations” against Russia that Mr Putin brushed off was London's assertion that former double agent Sergei Skripal and his daughter Yulia were poisoned in Salisbury with a Novichok military grade nerve agent from Russia.

Contrary to the findings of the Organisation for the Prohibition of Chemical Weapons, he insisted a lesser quality poison must have been used since they didn't die and demanded Moscow's officials be allowed to participate in the investigation.

In a video statement last month, Yulia Skripal said she and her father were recovering but declined the Russian embassy's requests for access to her Credit: Dylan Martinez/AFP/Getty Images

Asked about the Syria conflict, Mr Putin said Russia had ceased combat missions but would keep troops there “as long as it's advantageous,” seemingly walking back his December declaration that most forces would return home.

The call-in show allows Mr Putin to demonstratively order up solutions to problems like a flooded home or an underfunded hospital while passing the blame on to his underlings.

In a first, ministers and the heads of the country's 85 regions had to wait nervously on camera in their offices for the entire duration in case the president called on them.

The closely guarded Russian leader was briefly at a loss for words when the two television presenters began asking personal questions like “When did you first start believing in God?”

Asked what was the last good joke he'd heard, Mr Putin said he'd have to think about it, then switched back into attack mode.

“One of the most famous and popular publications in Germany recently wrote that Trump was pushing Europe into Putin's hands,” he said. “If you take this into account with the earlier joke that Russia influenced the US election, it all sounds pretty funny.”

Russia's governors are literally on camera as Putin starts his call-in show taking complaints. This is why there's a phrase in Russia, "The situation is worse than a governor's" https://t.co/c6sKlsI9sxpic.twitter.com/ytgqeLOXL1

— Alec Luhn (@ASLuhn) June 7, 2018

The initial question came in the form of a video shot by driver Alexei Karavayev in the cab of his lorry in St Petersburg and touched on what hosts had said would be one of the main topics of the show.

“Vladimir Vladimirovich, please tell us, how much higher will petrol prices go? Forty-five roubles for a litre of diesel, it's impossible!” he said.

“I agree, what's going on is impermissible, it's not right, but we need to admit it's not the result of soft regulation in the energy sphere,” Mr Putin responded, before launching into an explanation of the measures that the government had been taking to cut prices.

Another early topic was the World Cup, which kicks off in Russia next Thursday. A planned question from well-known football trainer Valery Gazzaev devolved into the manager invoking several Orthodox saints and repeatedly wishing Mr Putin good health.

The president nonetheless spoke about the legacy of the tournament, warning that the stadiums built in 11 cities shouldn't become white elephants but rather help to "develop a new generation of football players".

Russians watch Mr Putin's question-and-answer session while driving over a new bridge to Crimea, which was covered at length during the show Credit: Sergei Malgavko/TASS via Getty Images

Russia's highly centralised political system means Mr Putin's words carry great weight. He previously appointed governors for approval by regional parliaments, and the Kremlin still enjoys the last year over who the ruling party puts forward for election.

A televised tongue-lashing from Mr Putin can typically kick off activity amid even the most intractable bureaucracy. In past years, regional officials have begun scrambling to address problems before the call-in show even ends, worried for their security of their jobs.

Responding to a mother of three children who asked why she had been waiting already eight years for free land promised to large families, Mr Putin called up the governor of her region, who promised to take care of the problem.

“We should strive so that every family had at least three children, we should facilitate families like yours,” Mr Putin said, in a reference to the concern over population decline in the past two decades.

3:07PM

Putin says he's 'always thinking' about a successor

The call-in show finished after four hours and 20 minutes, during which Mr Putin answered 73 questions.

The length was not record-setting but must have felt like an eternity for the country's governors and ministers sitting at the ready on camera in case Mr Putin called on them.

In one of the final questions, Mr Putin, who has been in power since 2000, was asked if he was preparing a successor. He said he was "always thinking about this" but that the Russian people would in the end choose his successor.

He was re-elected to a six-year term in March.

Video: Putin Says He Won't Go for a 3rd Term as President

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2:07PM

Russia won't exchange Crimean political prisoner Sentsov for Russian reporter

Oleg Sentsov in a defendant's cage during his 2015 trial, which was called unfair by Amnesty International Credit: Sergey Venyavsky/AFP/Getty Images

Vladimir Putin rejected a suggestion that Russia could exchange film director Oleg Sentsov, who is serving 20 years in an Arctic prison for allegedly planning to blow up a Lenin monument in Crimea, for a Russian state media reporter detained in Kiev.

Mr Sentsov has been on hunger strike since May 14 to demand the release of other Ukrainian prisoners. Amnesty International has called his trial "unfair" and demanded his release.

RIA Novosti reporter Kirill Vyshinsky, who has both Russian and Ukrainian citizenship, was detained last month on treason charges.

"Mr Sentsov was detained in Crimea not for journalistic activity, but for preparing terrorist act, an explosion in which people could have suffered," Mr Putin said. "It's a different thing, not equivalent at all."

1:48PM

Russia won't withdraw from Syria yet

Mr Putin said the Russia military has ceased combat missions in Syria because there is “no need for them,” with most populated areas under the control of Bashar Assad's regime.

But Russian troops will remain at the naval and airbase in Syria “as long as it's advantageous,” he added, seemingly walking back his December declaration that most of the forces in Syria would return home.

He also rehashed the list of fantastic-sounded new weapons he announced in March, including a laser weapon, nuclear missiles and a nuclear-powered cruise missile and underwater drone.

The Mach 20 Avant-Garde missile is already in production, proving those who doubt Russia's military might wrong, he said.

“I don't think this weapon will appear among other country in coming years,” he said.

Putin says that Russia has ceased "large-scale military actions in Syria" because there's "no need for them". But troops will remain "as long as it's in Russia's interests."

Compare to his declaration last year that Russia would begin withdrawing its troops pic.twitter.com/8e3gvLecK9

— Alec Luhn (@ASLuhn) June 7, 2018

12:57PM

Accusations that Russia interfered in 2016 US election a 'joke'

The Russian leader was briefly stumped by a string of personal questions from the show's hosts, who asked him when he first started believing in God and what was the last good joke he heard.

After saying he'd have to think about it, Mr Putin suddenly went into another refutation of the accusations that Russia interfered in the 2016 election in the United States.

“One of the most famous and popular publications in Germany recently wrote that Trump was pushing Europe into Putin's hands. If you take this into account with the earlier joke that Russia influenced the US election, it all sounds pretty funny," Mr Putin said. "We supposedly influenced the election of the president of the United States, and he gave us Europe for it. It's total nonsense, you can't call this anything but a joke."

A string of personal questions seem to have caught Putin totally off-guard:

What advice would you give your grandchildren? When did you start to believe in God? What's the last good joke you heard?

"I don't know, I'd have to think" pic.twitter.com/R0Yels1MF8

— Alec Luhn (@ASLuhn) June 7, 2018

12:40PM

Putin calls for 'many steps forward' in new space race

A Soyuz rocket takes off from Russia's new Vostochny cosmodrome in November. It later crashed into the sea due to human error Credit: Marina Lystseva/TASS

Russia's efforts to raise its standing on the world stage have included a return to the space race, a sphere that has been re-energised by private firms in the United States and elsewhere.

With a nod to the Soviet Union's early successes in this area, Mr Putin declared Russia “should take many steps forward in the quality of satellites and equipment”.

He pledged that it would launch 600 satellites within the next few years to “replace cable communications” and would test a super-heavy rocket by 2022.

Despite sanctions, American and Russian scientists are working together to study deep space, he added.

Russia's space agency previously announced a project with NASA to build a base on the moon.

Despite the stress on space exploration, Russian rockets have suffered humiliating accidents in recent years. In November, a rocket carrying a $45m satellite and smaller satellites from several countries crashed into the sea after it was programmed with coordinates for the wrong launch site.

12:23PM

Uncomfortable questions don't always receive an answer

The focus on reaching web users has sometimes led to embarrassing kinks in the finely oiled machine of the call-in show.

As Mr Putin spoke, questions being submitted online were flashing on screens behind him, apparently without always being screened first.

"Why is there money for tanks, bombs, planes and machine guns in this country, but not for people?" read one.

The hosts and Mr Putin ignored the question.

For some reason, organisers continue to let sharp public questions shown in background. “Why is there money for tanks, bombs, planes, machine guns and no money for people?” pic.twitter.com/v152Mxh8ss

— Oliver Carroll (@olliecarroll) June 7, 2018

12:00PM

Putin again denies that Novichok was used in Skripal attack

Vladimir Putin was also asked if he would “respond to the accusations” from the UK that Russia was behind the poisoning of former double agent Sergei Skripal and his daughter Yulia in Salisbury.

Mr Putin demanded that Russia be allowed to participate in the British investigation.

He again denied that a military grade nerve agent had been used in the attack, even though the Organisation for the Prohibition of Chemical Weapons has confirmed the British government's finding that the military nerve agent Novichok was used.

“These people would have died at the scene within minutes. This didn't happen,” Mr Putin said. “We are dealing with something else, not a military nerve agent, but we would want to get access to our citizens, to Yulia in this case, and to have the chance to completely participate in investigation.”

Yulia Skripal, who is recovering in a secret location, has declined offers to meet with the Russian ambassador in London in written and video statements.

Moscow has called the UK allegations a “provocation” and “political campaign,” ridiculing Theresa May's statement that it was “highly likely” Russia was behind the attack.

State television has muddied the water by airing claims that the Skripals could have suffered food poisoning and asking why Sergei Skripal's pets were put down after the incident.