North Korea has said they are not interested in diplomatic solutions to its tensions with the US until it develops a missile capable of reaching the east coast of America.

A North Korean official confirmed Pyongyang's strategy to CNN, adding that "before we can engage in diplomacy with the Trump administration, we want to send a clear message that the DPRK has a reliable defensive and offensive capability to counter any aggression."

The latest comment adds to the increasing tension between the US and the isolated Asian nation with its seemingly mercurial leader Kim Jong Un.

Donald Trump has publicly traded insults with him, giving him the nickname "Rocket Man" and referring to him as such during the president's speech in front of the United Nations General Assembly.

He adding that the North Korean leader was “on a suicide mission” in continuing to develop a nuclear weapons programme.

Mr Kim’s state news agency then issued a statement in which they referred to Mr Trump as a “dotard."

Just last week Pyongyang warned Mr Trump's "reckless moves" could hurt Guam, the US territory island in the Pacific approximately 2,100 miles (3,425 km) southeast of North Korea.

North Korea propaganda video shows missiles blowing up US targets

Mr Trump had recently tweeted that Secretary of State Rex Tillerson was "wasting his time" trying to negotiate with Mr Kim through State Department diplomatic backchannels.

He tweeted that "only one thing will work" to deter North Korea's development of its nuclear arsenal, in yet another indication the president thinks military action is the only option left.

Mr Tillerson for his part attempted to reassure the American public on Sunday that "diplomatic efforts will continue until the first bomb drops," seeming to indicate the US would only strike as a retaliatory measure.

He also said there is no “better partner than Secretary of Defence who believes in diplomacy” regarding James Mattis' belief that military action should be a last resort.

Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Show all 6 1 /6 Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Photos released by North Korea show Kim Jong-un talking to subordinates next to a device thought to be the new thermonuclear weapon. There is no way of independently verifying the pictures STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korea claims it has successfully tested an advanced hydrogen bomb which could be loaded onto an intercontinental ballistic missile AFP/Getty Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A diagram on the wall behind Mr Kim shows a bomb mounted inside a cone STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korean leader Kim Jong-Un (C) attending a photo session with participants of the fourth conference of active secretaries of primary organisations of the youth league of the Korean People's Army (KPA) in Pyongyang STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters

The Defence Secretary has also stressed the "iron-clad" commitments of the US to allies like South Korea and Japan and reiterated his commitment to diplomatic options in in a statement given in front of the White House on 3 September.

However, he also said "any threat to the US", its territories like the Pacific island of Guam, or its allies would be met with a "massive military response ... both effective and overwhelming."

The United Nations Security Council, spurred by bold rhetoric from US Ambassador Nikki Haley, imposed the strictest-ever sanctions on the hermit kingdom.

The latest round sanctions impose caps on North Korea’s oil exports, bans all textile exports, and no country is allowed to issue work permits to those holding North Korean passports. Countries will also be allowed to freeze assets of cargo ships if they refuse to undergo inspections.

China, one of Pyongyang's biggest trading partners, has also announced it will no longer open new accounts for North Korean citizens or accept its currency after facing criticism for laundering North Korean money.

Last month, a US intelligence official said they had no reason to doubt Mr Kim and his military had developed a hydrogen bomb. The US official said, however, it would take some time to complete a thorough analysis of the size of the blast and type of device detonated during the last North Korean test.

In July, US intelligence officials said they believed North Korea had been able to make a nuclear warhead capable of fitting on an intercontinental ballistic missile – claiming missiles will have the range to reach the US. Recently, Pyongyang also launched a missile over the Hokkaido island of Japan.

South Korea has been preparing for a possible nuclear attack by running drills for residents, including the 120,000 Americans stationed on military bases in the country.