VIENNA, Oct. 10 (Xinhua) -- Argentina's candidate for the next chief of the United Nations nuclear watchdog had a narrow lead in a straw poll conducted by the International Atomic Energy Agency (IAEA) Board of Governors here on Thursday.

Rafael Mariano Grossi, Argentina's ambassador to the IAEA, ranked first with 15 votes, followed by Cornel Feruta of Romania (14 votes), Lassina Zerbo of Burkina Faso (4 votes), and Marta Ziakova of Slovakia (0 vote), according to the IAEA's official website.

"With a view to facilitating consensus," the IAEA Board of Governors conducted the straw poll as part of the ongoing informal consultations related to the appointment process, said the IAEA.

Straw polls give the Board of Governors a reading of the support enjoyed by the different candidates and are non-binding, said the IAEA.

The four candidates were nominated by their governments in accordance with the procedures for appointing a director general agreed by the Board of Governors on Aug. 1 after the passing of Director General Yukiya Amano, it said.

The Board of Governors expects to appoint a director general in October and envisages that the person appointed will assume office no later than Jan. 1, 2020, it said.

In order to be appointed, a candidate must secure two-thirds majority support in IAEA's 35-member Board of Governors. If a two-thirds majority is not achieved, the nomination process begins again.

The IAEA Board of Governors appoints the new director general for a term of four years. Its decision will be submitted for approval to the IAEA General Conference, which consists of representatives of all 171 member states.