United Nations Secretary-General Antonio Guterres said on Thursday that the billions of dollars the United States owes to the world body is “non-negotiable”, after reports that ​Washington had placed conditions on releasing the funds.

The development newswire Devex reported ‌this week that two diplomatic notes circulated by the US called for nine “quick-hit” reforms as a condition for releasing more funds, including further cost-cutting, and moves to counter China’s influence at ​the United Nations.

“The money we are talking about is referred to as ​assessed contributions,” Guterres told reporters when asked about the reports. “Assessed contributions ⁠are an obligation of member states. They are non-negotiable.”

Guterres, who has been leading ​reform efforts under pressure from member states, especially the US, said the ​UN would do its best “to make sure that we make this organisation as effective and as cost-effective and as able to deliver for the people we care for”.

“But these are two separate ​things,” he added.

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According to Devex, the US-demanded cost-cutting included overhauling the UN pension ​system, ending long-distance business-class travel for some senior and all mid-level professionals, additional cuts to ‌senior UN ⁠ranks and a 10% reduction in long-running and ineffective peacekeeping missions.

It said they also included a demand to block China from channelling tens of millions of dollars each year to a discretionary fund housed in the office of the UN ​secretary-general, a move aimed ​at countering Chinese ⁠influence.

The US mission to the United Nations has not commented on the reports. The US has said repeatedly it will keep ​pressuring the UN to reform after announcing its withdrawal ​from dozens ⁠of UN bodies this year and cutting millions of dollars in funding last year.

Guterres warned in January that the UN faced “imminent financial collapse” due to unpaid fees, most ⁠of which ​are owed by the US. The UN ​said in February that the US had paid about $160 million of the more than $4 billion it owes ​to the world body.