Donald Trump has warned that 'North Korea is looking for trouble', insisting that if China 'does not decide to help', the US 'will solve the problem without them'.

The US President wrote the extraordinary message on Twitter after revealing he had urged his Chinese counterpart Xi Jinping to pressure Pyongyang in to stopping its nuclear programme.

His warning came as Russia admitted it is 'extremely worried' the US will attack Kim Jong-Un after North Korea warned it has US bases 'in its nuclear sights'. Pyongyang had earlier threatened 'catastrophic consequences' after Trump sent an armada of warships to the Korean Peninsula.

At the same time, China has moved 150,000 troops to its border to deal with a possible influx of North Korean refugees amid fears Trump may strike Kim Jong-un following the surprise US missile attack on Syria last week.

G7 nations today insisted President Bashar al-Assad must step down as part of any peace solution in war-torn Syria and US Secretary of State Rex Tillerson declared it was clear that the 'reign of the Assad family is coming to an end'.

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Donald Trump has warned that 'North Korea is looking for trouble', insisting that if China 'does not decide to help', the US 'will solve the problem without them'

The US President wrote the message on Twitter after revealing he had urged his Chinese counterpart Xi Jinping to pressure its neighbour and close ally in to stopping its nuclear programme

Russia admitted it is 'extremely worried' the US will attack Kim Jong-Un (pictured at a Supreme People's Assembly in Pyongyang today) after North Korea warned it has US bases 'in its nuclear sights'

Pyongyang had earlier threatened 'catastrophic consequences' after Trump sent an armada of warships to the Korean Peninsula. North Korean officials are pictured applauding Kim Jong-Un as he presided over his parliament today

War games: Pyongyang condemned Washington's order to dispatch the USS Carl Vinson aircraft carrier and its battle group to the region for US-South Korea military exercises. A row of F18 fighter jets are pictured on the deck of the USS Carl Vinson

The Chinese army has deployed 150,000 troops to the Yalu River Bridge at the North Korean border in anticipation of a wave of refugees from North Korea if war breaks out. Meanwhile, the US Navy has moved the USS Carl Vinson aircraft carrier strike group from Singapore to the North Korean peninsula

The U.S. Navy aircraft carrier USS Carl Vinson, the guided-missile destroyer USS Wayne E. Meyer and the guided-missile cruiser USS Lake Champlain are pictured in March this year. North Korea has warned it is 'ready to react to any mode of war desired by the U.S.'

Last week, North Korea waded into the row over Syria by branding Trump's missile strike on an airbase in the war-torn country as 'an unforgivable act of aggression'.

The US took action after 87 Syrian civilians were killed in a horrific chemical attack that Washington blamed on Assad's forces. Russia - which has backed the Syrian dictator's military - as well as Iran and its allies then said the US had crossed a 'red line' and warned they 'will respond to any aggression' in the future.

This morning, North Korea warned of a nuclear attack on the US at any sign of pre-emptive action.

Pyongyang's state newspaper said the country was prepared to respond to any aggression.

'Our revolutionary strong army is keenly watching every move by enemy elements with our nuclear sight focused on the U.S. invasionary bases not only in South Korea and the Pacific operation theatre but also in the U.S. mainland,' the Rodong Sinmun newspaper said.

But South Korean officials today moved to quell fears on social media of an impending security crisis or outbreak of war.

'We'd like to ask precaution so as not to get blinded by exaggerated assessment about the security situation on the Korean peninsula,' Defence Ministry spokesman Moon Sang-kyun said.

Escalating tensions over both the threat posed by North Korea and the crisis in Syria have sparked fresh fears the world is heading towards a new global war.

Russian President Vladimir Putin today said he had information of future chemical weapons 'provocations' in Syria that would be used to frame Kremlin ally Bashar al-Assad.

Russian President Vladimir Putin (pictured today) said he had information of future chemical weapons 'provocations' in Syria that would be used to frame Kremlin ally Bashar al-Assad

Last week, North Korea waded into the row over Syria by branding Trump's missile strike on an airbase in the war-torn country as 'an unforgivable act of aggression'. Syrian dictator Basha al-Assad is pictured

G7 nations insisted Bashar al-Assad must step down as part of any peace solution in war-torn Syria and as US Secretary of State Rex Tillerson declared it was clear that the 'reign of the Assad family is coming to an end'. G7 officials are pictured as they gathered in Italy today

Standing alongside Italian President Sergio Mattarella who was in Moscow for talks, Putin said: 'We have information that a similar provocation is being prepared ... in other parts of Syria including in the southern Damascus suburbs where they are planning to again plant some substance and accuse the Syrian authorities of using (chemical weapons).' He did not offer any proof for that assertion.

Putin also said he will appeal to the United Nations to investigate last week's chemical attack in Syria, which claimed 87 lives and prompted Trump's surprise cruise missile attack.

'It reminds me of the events in 2003 when U.S. envoys to the Security Council were demonstrating what they said were chemical weapons found in Iraq,' Putin told reporters on Tuesday. 'We have seen it all already.'

Russia's foreign ministry says it hopes for 'productive talks' with U.S. Secretary of State Rex Tillerson, as he heads to Moscow in his first visit as the top US diplomat.

At the end of the week three-way talks are then planned in Moscow between the foreign ministers of allies Russia, Syria and Iran.

The Pentagon revealed on Saturday night that the USS Carl Vinson aircraft carrier and its battle group had been dispatched to the region for US-South Korea war games.

Last night, a spokesman for North Korea's foreign ministry said: 'This goes to prove that the U.S. reckless moves for invading the DPRK have reached a serious phase,' said a spokesman for the secretive nation's foreign ministry.

US Marine Corps are pictured during a joint defence exercise against a possible attack from North Korea, in Pohang, South Korea, on Tuesday

South Korean marine soldiers stand guard during the US-South Korea joint Exercise Operation Pacific Reach in Pohang, South Korea, on Tuesday

The joint defence excercises between US and South Korean Marine teams began on Tuesday, in Pohang, 360 km southeast of Seoul

'The DPRK is ready to react to any mode of war desired by the U.S,' he added.

'We will hold the U.S. wholly accountable for the catastrophic consequences to be entailed by its outrageous actions,' the North Korean foreign ministry spokesman said, adding that Pyongyang would respond to 'provocateurs' with a 'powerful force of arms'.

'We will take the toughest counteraction against the provocateurs in order to defend ourselves by powerful force of arms,' the foreign ministry spokesman said, according to KCNA.

The statement from Pyongyang comes as tensions on the divided peninsula are already high because of U.S.-South Korea wargames now underway and recent ballistic missile tests by the North.

Pyongyang sees the annual manoeuvres as a dress rehearsal for invasion, while the North's long-range missile launches are a violation of U.N. resolutions.

Aircraft carrier Carl Vinson and its wing of fighter jets were scheduled to make port visits in Australia but were diverted to waters off North Korea after the country conducted more missile testing, the Pentagon revealed on Saturday night.

A US marine is pictured in South Korea on Tuesday. South Korean and US military Combined Forces Command is holding the Combined Joint Logisics Over-the-Shore

US Marine Corps participate during a joint defence exercise against a possible attack from North Korea, in Pohang, on Tuesday

Trump said today that he tried to persuade China's leader Xi Jinping to pressure North Korea to stop its nuclear programme in exchange for a good trade deal with the US.

Mr Trump tweeted on Tuesday: 'I explained to the President of China that a trade deal with the U.S. will be far better for them if they solve the North Korean problem!'

In a second tweet he wrote: 'North Korea is looking for trouble. If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A.'

The president made clear his hope that China will pressure its neighbour and close ally to stop its nuclear programme.

He has also repeatedly attacked China for exporting more goods to the US than it imports.

The Chinese army has reportedly deployed 150,000 troops to the North Korean border to prepare for pre-emptive attacks after the United States dropped airstrikes on Syria.

President Donald Trump's missile strike on Syria on Friday was widely interpreted as a warning to North Korea.

And now China, left shocked by the air strikes, has deployed medical and backup units from the People's Liberation Army forces to the Yalu River, Korea's Chosun.com reported.

The troops have been dispatched to handle North Korean refugees and 'unforeseen circumstances', such as the prospect of preemptive attacks on North Korea, the news agency said.

South Korean acting President Hwang Kyo-ahn warned of 'greater provocations' by North Korea and ordered the military to intensify monitoring and to ensure close communication with the United States.

'It is possible the North may wage greater provocations such as a nuclear test timed with various anniversaries including the Supreme People's Assembly,' said Hwang, acting leader since former president Park Geun-hye was removed amid a graft scandal.

The North convened a Supreme People's Assembly session on Tuesday, one of its twice-yearly sessions in which major appointments are announced and national policy goals are formally approved.

Mr Trump hosted Chinese leader Xi Jinping for a summit at which he pressed Pyongyang's key ally to do more to curb the North's nuclear ambitions

Saturday is the 105th anniversary of the birth of Kim Il Sung, the country's founding father and grandfather of current ruler, Kim Jong Un.

A military parade is expected in the North's capital, Pyongyang, to mark the day. North Korea often also marks important anniversaries with tests of its nuclear or missile capabilities in breach of U.N. Security Council resolutions.

Syrian President Bashar al-Assad sent a message of congratulations to mark the event, lambasting 'big powers' for their 'expansionist' policy.

'The friendly two countries are celebrating this anniversary and, at the same time, conducting a war against big powers' wild ambition to subject all countries to their expansionist and dominationist policy and deprive them of their rights to self-determination,' Russian news agency Tass quote the message as saying.

North Korea and the rich, democratic South are technically still at war because their 1950-53 conflict ended in a truce, not a peace treaty. The North regularly threatens to destroy the South and its main ally, the United States.

Delegates from around the North have been arriving in Pyongyang ahead of the assembly session. They visited statues of previous leaders Kim Il Sung and his son, Kim Jong Il, state media reported.

Tensions continue to escalate over both the threat posed by North Korea and the crisis in Syria amid fresh fears the world is heading towards a new global war

WHO SUPPORTS WHO IN THE BATTLE FOR SYRIA? PRO ASSAD Russia - Gives military support, condemns the US airstrikes and suspends deal not to clash mid-air Iran - Close strategic allies with Syria and has provided significant support including $8.69billion North Korea - UN probe found that North Korea was supplying arms to Syria Iraq - The Iraqi Government provided financial support and transported supplies Algeria - Rumours suggest Algerian military aircraft is regularly landing in Syria Venezuela - The South American country has shipped tens of millions of dollars worth of diesel to Syria Lebanon - Police arrested family after they protested about the Syrian Government Belarus - President Alexander Lukashenko supported Moscow's involvement and offered air strike Lebanese Hezbollah Party - Involvement has been substantial and has deployed troops since 2012 ANTI ASSAD US - President Donald Trump launched first airstrikes since six-year civil war started UK - Supports US cruise airstrikes as Theresa May said chemical attack was 'despicable' France/Germany - Both of the countries today said Assad bears 'sole responsibility' for US strike Turkey - Opposed to Assad but objects to Syrian rebels and wants control of Kurdish area Canada - Canada gave more than $4.97million to the Syrian opposition in 2013 Saudi Arabia - The Middle East country is the main group to finance the rebels and has provided a large amount of weapons Israel - Prime Minister Benjamin Netanyahu was the first to praise the US's retaliatory attack, saying he 'fully supports' Donald Trump's decision to launch the cruise missile attacks Qatar- It was reported Qatar gave the Syrian rebels $2.98 billion at the start of the civil war in 2011 Advertisement

China's top nuclear envoy arrived in Seoul on Monday for talks on the North Korean threat, as the United States sent the naval strike group to the region and signalled it may act to shut down Pyongyang's weapons program.

Speculation of an imminent nuclear test is brewing as the North marks major anniversaries including the 105th birthday of its founding leader on Saturday - sometimes celebrated with a demonstration of military might.

Wu Dawei, China's Special Representative for Korean Peninsula Affairs, met with his South Korean counterpart on Monday to discuss the nuclear issue.

The talks come shortly after Mr Trump hosted Chinese leader Xi Jinping for a summit at which he pressed Pyongyang's key ally to do more to curb the North's nuclear ambitions.

'(We) are prepared to chart our own course if this is something China is just unable to coordinate with us,' US Secretary of State Rex Tillerson said after the summit.

He added however that Beijing had indicated a willingness to act on the issue.

'We need to allow them time to take actions,' Tillerson said, adding that Washington had no intention of attempting to remove the regime of Kim Jong-Un.

The meeting between Xi and Trump came on the heels of yet another missile test by the North, which fired a medium-range ballistic missile into the Sea of Japan on Wednesday.

Pyongyang is on a quest to develop a long-range missile capable of hitting the US mainland with a nuclear warhead, and has so far staged five nuclear tests, two of them last year.

'(We) are prepared to chart our own course if this is something China is just unable to coordinate with us,' US Secretary of State Rex Tillerson said after the summit (Mr Trump pictured with Xi Jinping)

Mr Trump is pictured with Chinese President Xi Jinping in Florida on Friday

Satellite imagery analysis suggests it could be preparing for a sixth, with US intelligence officials warning that Pyongyang could be less than two years away from its goal of striking the continental United States.

China, the US, South Korea and Japan all have dedicated envoys who meet at regular intervals to discuss the North Korean issue: a legacy of the long-stalled six-party process that also involved Pyongyang and Moscow. The North quit the negotiations in 2009.

The isolated North is barred under UN resolutions from any use of ballistic missile technology, but repeated rounds of sanctions have failed to arrest its nuclear ambitions.

President Donald Trump's national security adviser General HR McMaster on Sunday said North Korea was engaging in 'provocative behaviour'.

'This is a rogue regime that is now a nuclear-capable regime. The president has asked to be prepared to give him a full range of options to remove that threat to the American people and to our allies and partners in the region,' he told FOX News Sunday.

China has deployed medical and backup units from the People's Liberation Army (pictured above) forces to the Yalu River following President Donald Trump's missile strikes on Syria last week

Trump has previously threatened unilateral action against the reclusive state, a threat that appeared more palpable after Thursday's strike on a Syrian airfield following an apparent chemical attack.

Meanwhile, the United States has concluded Russia knew in advance of Syria's chemical weapons attack last week, a senior U.S. official said Monday.

The official said a drone operated by Russians was flying over a hospital as victims of the attack were rushing to get treatment.

Hours after the drone left, a Russian-made fighter jet bombed the hospital in what American officials believe was an attempt to cover up the usage of chemical weapons.

The official said the presence of the surveillance drone over the hospital couldn't have been a coincidence, and that Russia must have known the chemical weapons attack was coming and that victims were seeking treatment.