Sydney - Middle East Times Int’l: North Korean leader Kim Jong Un has arrived via rail in Russia to meet with President Vladimir Putin.

Mr Kim left Pyongyang for Russia on Sunday on his private train, North Korea's state media reported. It was not known where the leaders will meet, as Mr Kim's train is reportedly heading north, away from the city of Vladivostok.

A US official said they were expected to discuss an arms deal as Russia faces a Ukrainian counter-offensive.

The Kremlin said that the “fully fledged visit” would cover “bilateral relations, the situation in the region and in the global arena”. The meeting could take place as early as Tuesday local time although the statement from the Kremlin said it would happen in “coming days”.

Mr Kim left his train to meet Russian representatives when it pulled into the border station of Khasan on Tuesday. He met with Alexander Kozlov, Russia's minister for natural resources. 

Mr Kim's train is rumoured to include at least 20 heavy bulletproof carriages. The extra weight means the train is very slow; it can only travel at around 37mph (59 km/h).

The Vostochny cosmodrome, located in Russia's far east near the border with China, was suggested as the possible meeting place for the leaders. 

It is the country's first commercial space centre and is one of Mr Putin's pet projects.

The Russian president has announced he plans to go to the cosmodrome but has not confirmed that Mr Kim will meet him there. Responding to a question at the Eastern Economic Forum, Mr Putin said: “When I get there, you will know.”

North Korea may seek co-operation from Russia on its space program, which late last month failed for a second time to place a spy satellite in orbit.

The White House said it had new information that negotiations between the Russia and North Korea were on a weapons deal “actively advancing”.

National Security Council spokesman John Kirby said Russia’s Defence Minister Sergei Shoigu had tried to “convince Pyongyang to sell artillery ammunition” to Russia during a recent visit to North Korea; both sides denied the reports.

The US and its allies have expressed concern over the possibility of closer military ties between Russia and North Korea. 

Kremlin spokesman Dmitry Peskov said Russia would always act in its national interest.

“The interests of our two countries are important to us, not warnings from Washington,” he was quoted in Russian media.

North Korea also wants food aid and possibly technology to help its banned nuclear and missiles program, analysts said.