BUENOS AIRES/BRASILIA (Reuters) - Argentina and Brazil support the candidate nominated by Venezuelan opposition leader Juan Guaido to represent the country at the Inter-American Development Bank (IADB), officials in both governments told Reuters on Tuesday.

Guaido assumed the interim presidency in January after declaring President Nicolas Maduro’s 2018 re-election a fraud. He has nominated economist Ricardo Hausmann to represent Venezuela at the IADB.

A spokesman for Argentina’s Economy Ministry confirmed it would back Hausmann in a vote expected by the end of the week. In Brasilia, a Foreign Ministry spokesman said Brazil supported Guaido’s candidate.

Most countries on the IADB board are expected to back Hausmann except those that have not recognized Guaido, namely Mexico, Uruguay, Nicaragua, Bolivia and China, according to a bank official who asked not to be named.

Hausmann’s election to the IADB board would be the first example of Venezuela’s opposition government-in-waiting placing its own man at a major international institution.

Hausmann is a former Venezuelan planning minister who served as the IADB’s chief economist from 1994-2000. He teaches economic development at Harvard’s Kennedy School of Government.

The recognition of Hausmann adds to diplomatic pressure faced by Maduro to step down after months of political unrest. The United States said on Monday it will withdraw all remaining diplomatic personnel from Venezuela this week.

Venezuela is also grappling with a days-long electricity blackout that has crippled the OPEC member’s oil exports and left millions of citizens struggling to find food and water.