UNITED NATIONS, Dec. 19 (Xinhua) -- UN Secretary-General Antonio Guterres on Friday strongly condemned the arbitrary detention of 10 more UN personnel by the Houthis in Yemen, his spokesperson said.

"The Secretary-General calls for the immediate and unconditional release of all arbitrarily detained personnel from the UN, non-governmental and civil society organizations and diplomatic missions, and calls on the Houthis to rescind the referral of UN personnel for prosecution," spokesperson Stephane Dujarric said in a statement.

With the 10 people detained on Thursday, the total number of detained UN personnel in Yemen has risen to 69, he said.

The detentions render the delivery of UN humanitarian assistance in Houthi-controlled areas untenable, which directly affects millions of people in need and limits their access to life-saving assistance, Dujarric said.

Dujarric said the UN chief further called for the respect of international law, including the privileges and immunities of the United Nations and its personnel, which are essential to enabling humanitarian action in a secure and principled environment.

He added that the Secretary-General and the United Nations will continue sustained efforts with UN member states and the Security Council, as well as through direct engagement with the Houthis, to secure the release of all detained UN personnel. ■