The UN's political chief, Jeffrey Feltman, is in Kuwait for talks on ending the diplomatic crisis between Qatar and its Gulf neighbours.
The senior UN envoy stepped in as Arab states vowed to maintain their boycott of the emirate, jointly criticising its "negative" response to their list of demands to end the crisis.
Saudi Arabia and its allies the UAE, Egypt and Bahrain were meeting Wednesday in Cairo one month after they severed ties with Qatar, accusing Doha of supporting extremism.
Their list of 13 demands includes Doha ending support for the Muslim Brotherhood, closing Al-Jazeera, downgrading diplomatic ties with Iran and shutting down a Turkish military base in the emirate.
Feltman, who is UN under-secretary-general for political affairs, "is there currently to discuss with a broad range of interlocutors the ongoing crisis in the region and other conflicts," said UN spokesman Stephane Dujarric.
UN Secretary-General Antonio Guterres dispatched Feltman to the Gulf after meeting with Qatar's Foreign Minister Sheikh Mohammed bin Abdulrahman Al-Thani last week.
Feltman arrived in Kuwait from the United Arab Emirates and will travel to Doha later this week.
The United Nations has backed efforts by Kuwait to mediate an end to the crisis and has also offered to help broker a solution.
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