The US has tested an unarmed intercontinental ballistic missile from California, but the Air Force has stressed that it had nothing to do with recent tests conducted by North Korea.

The test was a routine operation according to the Air Force Global Strike Command spokesman Joe Thomas.

The missile was a Minuteman III, which was launched from Vandenberg Air Force base on Wednesday morning (3 May) and travelled about 4,200 miles which is just under double the distance between the base and Hawaii.

Linda Frost, a spokeswoman for strike command, said the missile is tested about four times a year.

"These test launches verify the accuracy and reliability of the ICBM weapon system, providing valuable data to ensure a continued safe, secure and effective nuclear deterrent," the strike command said in a statement.

"The ICBM test launch program demonstrates the operational capability of the Minuteman III and ensures the United States' ability to maintain a strong, credible nuclear deterrent as a key element of US national security and the security of US allies and partners," it added.

In recent weeks and months, tensions with North Korea have risen after the hermit nation attempted to perform a number of missile tests with mixed levels of success.