'America preparing military options in case sanctions fail'

Joseph Dunford said a "full range" of contingency plans had been drawn up in case diplomatic and economic sanctions did not deter Pyongyang's development of nuclear weapons.

The Joint Chiefs of Staff chairman told South Korean President Moon Jae-in of the preparations during a 50-minute meeting on Monday, according to a US military spokesman.

It comes amid heightened tensions over fears Pyongyang is close to achieving its goal of putting mainland US within range of a nuclear weapon.

The two nations exchanged military threats last week, with North Korea warning it has developed a plan to strike the US Pacific territory of Guam.

On Friday Donald Trump said military solutions to the crisis were "locked and loaded", days after vowing to unleash "fire and fury" if Pyongyang continued to threaten the US.

Dunford is visiting Seoul to discuss the rising tensions in the region with President Moon Jae-in and Defence Minister Song Young-moo ahead of major joint US-South Korean military drills scheduled for later this month.

"He conveyed America's readiness to use the full range of military capabilities to defend our allies and the US homeland," said US military spokesman Darryn James.

Dunford, who will also meet with leaders in Japan and China, "stressed that North Korea's ballistic missile and nuclear weapons programmes threaten the entire global community," the spokesman added.

Dunford had earlier told reporters he aimed to "sense what the temperature is in the region" and discuss military options in the event the "diplomatic and economic pressurisation campaign" fails.

"We're all looking to get out of this situation without a war," he added.

Moon separately called for a peaceful solution to the nuclear stand-off, urging that "there must not be another war on the Korean Peninsula".It comes as senior US officials attempted to provide assurances with that conflict with North Korea not imminent.