According to the port of Paranagua, the Iranian ship 'Bavand' set sail from Brazil after receiving fuel from Petroleo Brasileiro.
Another Iranian ship, the Termeh, set sail from Paranagua Port two days ago and will stop at the Brazilian port of Imbituba, where it will pick up a load of corn before returning to Iran.
Recently, Brazil's Chief Justice Dias Toffoli ordered the state-run oil company Petrobras to provide fuel to Iranian vessels carrying grain.
The ships had been waiting off the coast of the southern state of Parana since early June, as Brazil's state oil company refused to refuel them due to US sanctions on Iran.
The incident occurred amid an Iranian standoff with the UK, prompted by the seizure of an Iranian oil tanker in Gibraltar after it was suspected of carrying oil to Syria in violation of EU sanctions.
In turn, Tehran denied the allegations, and later the Islamic Revolutionary Guard Corps captured the UK oil tanker Stena Impero.
Tensions escalated last week when Iranian forces seized the UK-flagged Stena Impero oil tanker in the Strait of Hormuz.
The incident was allegedly Tehran's response to the seizure of an Iranian tanker by UK Royal Marines and the authorities of Gibraltar on 4 July.
The US-Iran relations have been in a downward spiral since the scrapping of the Iran Nuclear Deal by the Trump administration. Iran later announced that it would exceed the limits on enrichment set out in the JCPOA.