BEIJING (AFP, REUTERS) - A conflict over North Korea could break out "at any moment", China's foreign minister Wang Yi said Friday (April 14), warning there would be "no winner" in any war, as tensions soar with the US.

The sharp language came after President Donald Trump said that the "problem" of North Korea "will be taken care of", as speculation mounts that the reclusive state could be preparing another nuclear or missile test.

"Lately, tensions have risen with the US and the ROK on one side, and the DPRK on the other, and one has the feeling that a conflict could break out at any moment," Wang said, using abbreviations for South and North Korea.

"If a war occurs, the result is a situation in which everybody loses and there can be no winner," he said during a joint press conference with his French counterpart Jean-Marc Ayrault.

Wang said that whichever side provoked a conflict "must assume the historic responsibility and pay the corresponding price."

Trump has sent a aircraft carrier-led strike group to the Korean peninsula to press his point, one of a series of signals that indicate his willingness to shake up foreign policy strategy.

Implicit warning

The US military on Thursday dropped the biggest non-nuclear bomb it possesses on Afghanistan, targeting a complex used by the Islamic State in Iraq and Syria (ISIS) group. Trump also flexed his military muscle last week by ordering cruise missile strikes on a Syrian airbase the US believed was the origin of a chemical weapons attack on civilians in a northern Syria town.

The moves are seen as an implicit warning to North Korea that Washington is not afraid to use force.

Trump has repeatedly said he will prevent Pyongyang from its goal of developing a nuclear-tipped ballistic missile capable of reaching the mainland United States.

A White House foreign policy advisor said Friday that the US is assessing military options in response to the North's weapons programmes, saying another provocative test was a question of "when" rather than "if".

US ally South Korea warned against any North Korean "provocation".

"If North Korea conducts a strategic provocation such as a nuclear test or an intercontinental ballistic missile launch, there is certain to be powerful punitive measure that will be difficult for the North Korean regime to endure," the South's Foreign Ministry said in a statement.

North Korea for its part denounced the United States for bringing "huge nuclear strategic assets" to the region as the nuclear-powered USS Carl Vinson strike group steamed closer. A spokesman for the North Korean Foreign Ministry's Institute for Disarmament and Peace issued a statement condemning the United States for its attack on the Syrian airfield.

"The US introduces into the Korean peninsula, the world's biggest hot spot, huge nuclear strategic assets, seriously threatening peace and security of the peninsula and pushing the situation there to the brink of a war," the North's KCNA news agency said on Friday, citing the statement.

"This has created a dangerous situation in which a thermo-nuclear war may break out any moment."

North Korea, still technically at war with the South after their 1950-53 conflict ended in a truce, not a treaty, has on occasion conducted missile or nuclear tests to coincide with big political events and often threatens the United States, South Korea and Japan.

On Saturday, it marks the "Day of the Sun", the 105th anniversary of the birth of state founder Kim Il Sung, and there are reports of activity at a nuclear test site.

But Beijing has long opposed dramatic action against Pyongyang, fearing the regime's collapse would send a flood of refugees across its borders and leave the US military on its doorstep.

"Dialogue is the only possible solution," Wang said.

Russia calls for restraint

The Kremlin said on Friday it favoured diplomatic methods of resolutions of all crises, including on the Korean peninsula, amid mounting tensions between Washington and Pyongyang over North Korea's nuclear programme.

"We call all countries for restraint, we call all the countries to refrain from any actions that could amount to provocative steps", Kremlin spokesman Dmitry Peskov told a conference call with reporters.

Any US strike on North Korea could prompt retaliation against allies or US forces in South Korea or Japan.

But there are few good diplomatic or economic options for the Trump administration.

The North is already under multiple sets of United Nations sanctions over its nuclear and ballistic missile programmes, and appears to see these programmes as insurance against regime change.

Rattled by Trump's behaviour, Beijing - Pyongyang's sole major ally and economic lifeline - has adopted a tougher line against its neighbour, including suspending coal imports from the country for the remainder of the year.