The United Nations Security Council has passed a resolution significantly tightening sanctions on North Korea.

The decision, which was delayed on 1 March at the request of Russia, took place on 2 March and approved the mandatory inspection of all cargo entering and leaving the North, in addition to a blanket ban on Pyongyang exporting mineral resources.

Additional people and companies have also been added to the sanctions list, including the expulsion of North Korean diplomats partaking in sanctioned activities, while the sale of conventional weapons to the country is prohibited.

Put forward by the US, and with the support of China, the approved sanctions are believed to be far harsher than those previously imposed on Iran in order to limit the country's nuclear programme.

And the ruling on North Korea comes less than two months after Pyongyang declared it had carried out a successful test of a hydrogen bomb – although this was widely disbelieved at the time.

In a telephone interview with the Washington Post, the US ambassador to the United Nations Samantha Power said: "Irrespective of whether they change their calculus tomorrow, it's going to be a lot harder for them to access the technology, the know-how and the money they've used to fuel their nuclear programme.

"This is really going to dramatically increase the isolation of the regime, and increase the cost of maintaining this programme."

It is believed the sanctions are aimed at targeting the country's ruler Kim Jong-un and regime rather than poorer citizens, although it is not clear exactly how the harsher sanctions will affect people on the ground.