UN Secretary-General Antonio Guterres said on Monday he believed former Palestinian Prime Minister Salam Fayyad was the right person to be the world body's envoy to Libya after the United States raised objections.
US Ambassador to the United Nations Nikki Haley has expressed disappointment over Guterres's choice, saying the United Nations has for too long been "unfairly biased in favour of the Palestinian Authority to the detriment of our allies in Israel."
"It is a loss for the Libyan peace process and for the Libyan people that I am not able to appoint him," Guterres said at a summit in Dubai.
"I do not think there is any valid reason to avoid someone who is very competent to do a job that is extremely important," he said, adding that ending the Libyan conflict was in "everybody's interest."
It was unclear whether the US objection has ended Fayyad's candidacy. Guterres declined to answer questions when approached by Reuters immediately after his comments.
Guterres dismissed the accusation that the United Nations is biased on Israeli-Palestinian issues and said the body's only loyalty was to its charter.
"The UN needs to be able to act with impartiality in all circumstances and cannot be biased in favor of anybody," he said.
Guterres said the United Nations would have to engage with the administration of US President Donald Trump as it would "with any other administration."
Trump, while he was president-elect, criticised the United Nations as "just a club for people to get together, talk and have a good time" while a spokeswoman said the new administration would "demand some reform and change."
"Let's do everything possible to make this relationship a constructive relationship," Guterres said. "Having said so, we need to respect our values and we need to make sure a multilateral approach to global problems is valued."
A UN deputy spokesman, Farhan Haq, declined to say whether the US mission had endorsed Fayyad to the secretary-general and then reversed course at the last minute.
Haq told reporters only that Guterres had sought input from Security Council members before formally submitting his choice to them.
"He and the secretariat did consult prior to this. We believed we had the understanding in hand but we did not," Haq said in New York.
Guterres, on a tour of the Middle East, also praised Syria's main opposition body for approving a delegation to take part in peace talks on 20 February in Geneva.
The talks "are a first step for serious progress in finding a transition that allows for a political solution in which all Syrians feel represented," he said.
The High Negotiation Committee's decision to send a delegation follows indirect talks last month in Kazakhstan where Russia, Turkey and Iran agreed to monitor a fragile truce in Syria.