Brazil has expelled Nicaragua's ambassador, Fulvia Patricia Castro Matus, in retaliation for Managua's expulsion of Brazil's ambassador, Breno de Souza da Costa. Tensions escalated after Costa did not attend a July event marking the Sandinista Revolution, which angered Nicaraguan officials. This diplomatic spat underscores the deteriorating relations between the two countries, which were once allies under leftist governments. Brazilian officials cited the principle of reciprocity in their decision to expel Castro, as Nicaragua's government had previously ordered Costa to leave. The relationship soured further after failed mediation attempts by President Lula da Silva to secure the release of a jailed bishop, reflecting broader divisions in Latin American leftist politics. Observers suggest that this could lead to increased isolation for Nicaragua within the region.