The source was quoted as saying by Reuters that more than 100 UN staff were moving to the airport to be relocated to other countries, Jordan being one of them.
Earlier in the day, Saudi Arabian Defense Minister Prince Mohammed bin Salman Saud had sent three planes in order to evacuate a UN mission in Sanaa.
Also on Saturday, 86 Arab and Western diplomats were evacuated from the Yemeni port city of Aden by Saudi Arabia's navy, according to media reports.
Yemen is currently suffering from political unrest and clashes between Houthi rebels and loyalists of ousted President Abd Rabbuh Mansur Hadi.
On Wednesday, Hadi asked the Arab League for military aid and later in the day the Saudi Arabia-led coalition of countries began conducting airstrikes on Houthi positions in the Yemeni capital.