Vladimir Putin is sending troops and equipment to Russia's border with North Korea over fears the US is preparing to attack Kim Jong-un.

The Russian President fears there will be a huge exodus of North Korean refugees if his American counterpart, Donald Trump, launches military action against Pyongyang.

It comes days after it emerged that China is also sending 150,000 soldiers to its southern frontier to cope with the tidal wave of North Koreans Beijing fears would flee across the border if war breaks out.

This morning, footage emerged appearing to show how Putin is reinforcing his 11-mile border with North Korea by relocating troops and equipment.

Reinforcements: Vladimir Putin is sending troops and equipment to Russia's border with North Korea over fears the US is preparing to attack Kim Jong-un. Footage shows a train carrying Russian tanks to the border in the country's far south east

Vladimir Putin is reinforcing his border with North Korea by relocating troops and equipment, including helicopters (left) and tanks (right)

Russia is sending troops to its tiny border with North Korea while China is also understood to have sent 150,000 soldiers to its southern frontier amid fears of a refugee crisis in the event of war

A video purports to show one of three trains loaded with military equipment moving towards the 11 mile-long land frontier between Russia and the repressive state.

Another evidently highlights military helicopter movements towards the North Korean border and manoeuvres across rough terrain by army combat vehicles.

Other reports suggest there have been military moves by road as well.

There have been concerns that if a conflict breaks out Russia could face a humanitarian exodus from North Korea.

But Putin has been warned, too, that in the event of a US strike on Kim Jong-un's nuclear facilities, contamination could swiftly reach Russia.

'Railway trains loaded with military equipment moving towards Primorsky region via Khabarovsk have been noticed by locals,' reported primemedia.ru in the Russian far East - linking the development to the North Korean crisis.

'The movement of military equipment by different means of transport to southern areas is being observed across Primorsky region over the past week,' said military veteran Stanislva Sinitsyn.

Putin (pictured) has reportedly been warned that in the event of a US strike on Kim Jong-un's nuclear facilities, contamination could swiftly reach Russia

Another clip highlights military helicopter movements towards the North Korean border and manoeuvres across rough terrain by army combat vehicles

The movements of troops and equipment have been described as 'a preventive but necessary' measure.

'Many relate this to the situation in the Korean peninsula.

'The video shows artillery systems that either support troops in assault or meet the aggressor.'

He said: 'The movement of military equipment means that authorities of our country are keeping up with the situation - and take appropriate measures.'

The movements were 'a preventive but necessary' measure.

'If the situation worsens, especially related to military events, the armed forces of all the neighbouring countries obviously monitor it more closely, and we are no exception.

'It is not the first time that North Korea has broken the peace in the region, that's why this situation deserves attention.'

Russian military spokesman Alexander Gordeyev declined to give the exact reasons for the troop and equipment movements but said exercises had recently ended in the TransBaikal region of Siberia.

Kim Jong-un has threatened the US with a 'super-mighty preemptive strike' and warned America: 'Don't mess with us'

Thousands of goose-stepping troops paraded through Pyongyang in a show of strength on Saturday

Chilling: An enormous missile drives past troops during the Day of the Sun military parade on Saturday

However, a number of local sources appear to believe the movements are linked to the Korean crisis.

The naval port of Vladivostok - where Russia has huge military forces - is less than 100 miles from North Korea.

Expert on the repressive state, Konstantin Asmolov, said: 'Should the US strike with missiles at North Korea's nuclear facilities, a radioactive cloud will reach Vladivostok within two hours.'

Asmolov, from the Russian Far Eastern Institute, warned that in the event of full-scale war 'hungry asylum seekers will flood into Russia.'

Russia on Wednesday blocked UN Security Council condemnation of Pyongyang's latest missile test - even though China, which has a major frontier with North Korea had backed the strongly-worded statement put forward by the United States.

The proposed statement would have demanded that North Korea 'conduct no further nuclear tests' and halt missile launches .

Pyongyang carried out a failed test on Sunday.

Russia wanted to include language contained in a previous statement stressing the need to achieve a solution through dialogue, according to council diplomats.

Moscow's deputy foreign minister Sergei Ryabkov said: 'Unfortunately, we have to admit that the risk of a serious conflict in this region has substantially increased.'

He called for a 'demonstration of responsibility' from all sides to avoid escalation.