The Russian government has announced plans to carry out a series of joint army, navy and air force exercises with North Korea this year, another sign of the close relationship that is developing between the two nations that have been target of international criticism for their domestic and international activities in recent months.

Both Russia and North Korea have been the target of United Nations sanctions, with the UN attempting to halt Russian involvement in Ukraine's fighting. The UN also imposed restrictions on North Korea over its third underground nuclear test, carried out in February 2013, and a series of subsequent missile launches. North Korea's record on human rights is also being debated in the UN and it is possible that Kim Jong-un, the North Korean leader, could be cited in a case referred to the International Criminal Court.

For that to happen, however, the five permanent members of the UN Security Council would have to support the case. Russia, which holds a veto on the council, is now considered increasingly likely to support its new ally.

'In recent years, Beijing has come to see the regime in Pyongyang as increasingly troublesome,' says expert

Benefits of friendship

Analysts say there are benefits to the friendship for both sides.

"For Russia, cooperation with North Korea is beneficial purely as an economic relationship that transcends ideology but enables Moscow to diversify its trading partners," Daniel Pinkston, a Korea analyst with The International Crisis Group in Seoul, told DW.

"With its relationship with Europe and the West affected by what is going on in Ukraine, Moscow is turning to the east for opportunities in trade and investment," he said.

Vladimir Putin, the Russian president, is also to a degree thumbing his nose at an international community that has been fiercely critical of Kim Jong-un's regime in North Korea.

The benefits for Pyongyang seem more substantial.

"They need technology, investment, new infrastructure and energy, and the North Koreans are going to take it from wherever they can get it," said Pinkston. "They have a shared border and both sides are willing to deal."

No longer reliable

Yet another consideration for North Korea, points out Go Ito, a professor of international relations at Tokyo's Meiji University, is its troubled relationship with China.

For North Korea, China is no longer the reliable ally that it once was," he said. "The relationship has always been a delicate one, but in recent years Beijing has come to see the regime in Pyongyang as increasingly troublesome - particularly since Kim Jong-un came to power."

Kim took over from his father in December 2011 and is blamed for a number of provocations since then, including the nuclear test 15 months later.

Beijing has become frustrated and increasingly infuriated by Pyongyang's actions that are both aggressive and destabilizing, and China is understood to be pressuring the regime by limiting exports and assistance.

North Korea's response has been to look for new friends.

Last year, Russia announced that it was cancelling 10 billion USD of North Korea's 11 billion USD debts, and that the remaining 1 billion USD would be invested back into the country. Russian investors have also agreed to sink 25 billion USD into the North's dilapidated railway system, while more will go into basic infrastructure. The two governments more recently announced that Russia is to rebuild the North's power grid, while the two countries are developing the ice-free port of Rason for exports of Russian coal.

In total, Russia plans to increase bilateral trade almost ten-fold to 1 billion USD by 2020.

Kim to visit Moscow

Another demonstration of the burgeoning friendship between Putin and Kim is the North Korean leader's acceptance of an invitation to attend a ceremony in Moscow on May 9 marking the 70th anniversary of the end of World War II. With Russia still under international sanctions because of its role in Ukraine, many world leaders were expected to ignore its invitations to the event. The number of no-shows may increase if world leaders are expected to share the limelight with Kim.

The UN is attempting to halt Russian involvement in Ukraine's fighting

But it is the nascent military alliance between the two nations that is cause for concern in some circles. Marcus Nolan, the noted North Korea-watcher at the Peterson Institute for International Economics, notes that Kim is hungry for advanced military aircraft and that Putin might use the occasion of the Moscow celebrations to unveil the deal.

Kim's father, Kim Jong-il, attempted to sign a similar deal on Sukhoi Su-35 fighters during meetings with Russian leaders in 2001 and 2002, but Russia was on better terms with the West at that point and the transactions never went ahead. The situation today is very different.

"North Korea certainly needs spare parts for its military equipment, as well as more advanced weapons systems, so that is one reason for them approaching the Russians," agreed Pinkston. "But we must remember that Pyongyang is under UN sanctions on weapons sales, so for Russia to actually go ahead and sell advanced military systems to North Korea would be a very calculated move that would indicate Russia is defying the legitimacy of the UN and sanctions in general."

Given North Korea's adeptness in secret technology transfers, such as the sale or nuclear and missile technology to Syria and Iran, Pyongyang may well attempt to keep any purchases from Russia very quiet.