Story highlights A UN undersecretary-general resigned after a report said Israel was using apartheid-style practices on Palestinians

The report was compiled at the request of 18 Arab countries

Trump has made it quite clear that the US will defend Israel

(CNN) Memo to critics of Israel inside the UN system: Prepare to pay a price.

The sizeable impact of President Donald Trump's new administration on the UN reverberated again Friday when an undersecretary-general resigned after a UN agency report said Israel was using apartheid-style practices on Palestinians.

The US under Trump has made it quite clear it will defend Israel perhaps more than all other countries at the UN. So when what might have been an obscure report by a small UN group, among thousands printed through the UN, accused the Israeli regime of being "designed" for the core purpose of apartheid, diplomatic fireworks erupted.

New UN Secretary-General Antonio Guterres already has a tough road ahead because the United States, the UN's biggest financial contributor, wants to dramatically slash funding to the global organization and humanitarian programs. Guterres acted relatively quickly to distance the UN from the report -- which was compiled by the Economic and Social Commission for Western Asia at the request of 18 Arab countries.

On Friday, the UN said Guterres accepted the resignation of UN under-secretary general and the executive secretary of the commission that authored the report, Rima Khalaf.

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