The International Atomic Energy Agency (IAEA) is searching for a new chief following the death of its head, Yukiya Amano, in July.

Romanian diplomat Cornel Feruta, the organisation's acting director general since Amano's death, is running neck-to-neck with the Argentinian ambassador to the IAEA, Rafael Grossi, to replace Amano.

In an informal vote by the 35-member board of governors of the Vienna-based organisation, Feruta received 14 votes, while Grossi got 15 endorsements, the diplomat said.

A third candidate, Lassina Zerbo of Burkina Faso, got five votes. In total, 34 votes were cast.

Zerbo is the executive secretary of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), also based in Vienna.

A fourth candidate, Marta Ziakova, head of the Slovak Nuclear Regulatory Authority, has dropped out after she received no support in an earlier informal vote.

The procedure of appointing a new director general would ordinarily take around a year but a meeting of the IAEA's board of governors held after Amano's death agreed to an accelerated timetable, which should see a new head appointed in October.

No date for a formal vote has been set as yet. The new director general needs to secure two-thirds of the votes of the board of governors.

The IAEA is tasked with monitoring Iran's nuclear activities to ensure they abide by the terms of the 2015 deal known as the Joint Comprehensive Plan of Action.

This has veered towards the brink of collapse since the US dramatically withdrew in May 2018.