He entered the Holy See's diplomatic service in 1996 and held positions in
Korea,
Mongolia and the
Netherlands. Beginning in 2001 he served in the
Secretariat of State. On 17 August 2009,
Pope Benedict XVI appointed him
Undersecretary for Relations with States, replacing
Pietro Parolin who was named
Apostolic Nuncio to Venezuela the same day. On 22 February 2013, in the last week of the papacy of
Pope Benedict XVI, Balestrero was appointed apostolic nuncio to
Columbia and
Titular Archbishop of
Vittoriana. He received his episcopal consecration from Cardinal
Tarcisio Bertone on 27 April. In Colombia he supported the government's entente with the
FARC guérilla movement and the peace agreement reached in November 2016, leading to a papal visit to Colombia in 2017. Early in 2018, the Apostolic Nuncio to the
Democratic Republic of the Congo (DRC), Archbishop
Luis Mariano Montemayor, returned to Rome after being declared
persona non grata for his criticisms of DRC President
Joseph Kabila. On 6 July, the Holy See sent Balestrero to the nunciature in the DRC to resolve its affairs (
per il disbrigo degli affari), though he was not given a title in the nunciature. On 27 April 2019, after elections and a change of government in the DRC,
Pope Francis named Balestrero apostolic nuncio to the
Democratic Republic of the Congo. On 21 June 2023, Pope Francis appointed him as
Permanent Observer of the Holy See to the United Nations in Geneva. ==Notes==