Hundreds of Russian and Chinese tanks, attack helicopters, fighter jets and thousands of soldiers will this week fight side by side in the biggest war games in Russia since 1981, in a show of strength and friendship between Asia’s two largest military powers.

Russia’s biggest military exercise since the cold war, and its first to be conducted with a country not from the former Soviet bloc, is the strongest sign yet of the deepening strategic bond between Moscow and Beijing that has been prompted by Russia’s souring western relations and may herald a redrawing of the region’s geopolitics.

Involving 300,000 troops and close to 40,000 vehicles, the seven-day ‘Vostok’ war games will coincide with talks between Vladimir Putin and Xi Jinping in Vladivostok on Tuesday, amid a concerted effort by Russia to pivot east and embrace its powerful neighbour.

Alexander Gabuev, chair of the Russia in the Asia-Pacific Program at the Carnegie Moscow Center, said: “This is pretty huge. These major exercises are designed to simulate responses to aggression from external enemies.

“For decades, China has been considered one of those potential threats. Thus, to invite them to participate suggests that now they are seen as allies against other aggressors.”

China and Russia’s 4,200km border has been a source of friction for both countries over the past century, with multiple frontier conflicts.

But in recent years they have sought to develop stronger trade, energy, investment and security relations, with deals for Chinese banks to fund Russian energy projects, oil and gas supply agreements and corporate joint ventures.

That has been spearheaded by a personal friendship between Mr Xi and Mr Putin, and become more prominent since western sanctions were imposed on Moscow in 2014.

Florence Cahill, a senior analyst at GPW, a political risk consultancy, said: “Both Beijing and Moscow are looking to demonstrate that trade wars and sanctions will only push them to develop new alliances.

“As long as their prevailing worldview is shaped by an animus towards a US-led international order, co-operation on all levels between Moscow and Beijing will likely be more pronounced than competition between them.”

More than 3,200 Chinese troops and over 900 aircraft, helicopters and land equipment will take part in the vast exercises across Siberia and eastern Russia and waters off the country’s eastern coast.

Held once a year in each of Russia’s four military regions, the exercises rehearse an attack on a foreign power. In previous years they have simulated attacks on China and Poland.

Valery Gerasimov, chief of Russia’s general staff, said: “There are plans to practise massive air strikes, cruise missile training, defensive and offensive operations, raids, and bypass manoeuvres.

We are used to allegations that Russia is preparing for some big conflict . . . But there are absolutely no grounds for that

“Aircraft will practise support to an offensive mounted by ground forces and beach defence. Planes and helicopters will practise bombings and [the] use of air-launched missiles.”

While their militaries work together, Mr Xi and Mr Putin will meet at an economic conference in Vladivostok, alongside Japanese prime minister Shinzo Abe and South Korean prime minister Lee Nak-yeon.

The talks and the war games come at an uneasy time for the region, with uncertainty over the continued defence role of the US military, the fate of North Korea’s nuclear programme and Pyongyang’s enthusiasm for a settlement brokered by Donald Trump, the US president.

Kwon Hyuk-chul, a security expert at Kookmin University in Seoul, said the Sino-Russian drills could have an impact on denuclearisation efforts on the Korean peninsula.

“China’s participation in these drills is going to make the US uneasy,” he said. “If relations between China and the US continue to worsen, our efforts towards denuclearising North Korea could face a setback. Co-operation is what is most needed right now.”

Moscow has denied that the war games have been designed to prepare its forces for a large-scale conflict.

Maria Zakharova, a spokeswoman for Russia’s foreign ministry, said: “Unfortunately, we are used to the allegations that Russia is preparing for some big conflict. We have been hearing such statements from Nato representatives and some of its members. But there are absolutely no grounds for that.”

Aside from demonstrating the developing friendship between the two countries, defence analysts also say that the Vostok drills will allow both countries’ top brass to get a good look at their neighbours’ military equipment and tactics.

Mikhail Barabanov, editor-in-chief of the Moscow Defence Brief, said: “The Russian military, of course, is interested in seeing and assessing China’s progress in the military field.

“But I believe that for China the opportunity to get acquainted with the Russian armed forces is much more interesting, since the Russian army has in recent years a great deal of combat experience in Ukraine, Syria, etc while China’s armed forces are completely deprived of modern combat experience and have not fought since 1979.”

While politicians and businessmen are keen to continue searching for more areas of mutual assistance between China and Russia, generals in both countries are likely to be more circumspect given their history of animosity.

“I do not think the Russian general staff is so naive as to think this is a definite long-term alliance,” said Mr Gabuev. “There will naturally be mutual wariness. But the overarching strategic view regarding China has shifted.”

Additional reporting by Bryan Harris in Seoul

This article has been amended to correct the title of Shinzo Abe.

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