July 30 (Reuters) – A first informal U.N. Security Council poll on Thursday showed former Costa Rican ‌Vice President Rebeca Grynspan as the early frontrunner in the race to become the next secretary-general of the United Nations, followed by former Guyanese Foreign Minister Carolyn Rodrigues-Birkett, diplomats told Reuters.

Argentina’s Rafael Grossi, head of the U.N. nuclear watchdog, was in a surprise third place among the seven candidates for the post, a diplomat said. In the non-binding “straw poll” voting by ​the 15 members of the Security Council, Grynspan received 10 “encourage” votes to nine for Rodrigues-Birkett and seven for Grossi.

The candidates are seeking ​to replace Antonio Guterres of Portugal when he steps down at the end of this year after two five-year ⁠terms.