(Adds detail of Brazilian refinery projects, more comment on Iranian plans, Petrobras links)

BRASILIA, Feb 11 (Reuters) - Iran and Brazil are in talks about a possible Iranian investment in troubled refinery projects controlled by Brazilian state-led oil company Petroleo Brasileiro SA , a Brazilian government source told Reuters on Thursday.

Iran, which is boosting oil output after the end of sanctions over its nuclear program, is interested in exporting oil to Brazil, processing that crude at refineries in Brazil's northeastern region and then selling it in the Brazilian market, the source said, adding that talks are at an early stage.

Talks though are far from any result, the source added.

"For this subject to be considered embryonic it will still need to evolve a lot," said the source, who asked for anonymity because the inter-government talks are private.

Iran has shown interest in investing in the construction of the Premium I and Premium II refineries in Brazil's northeastern states of Maranhao and Ceara, the source said. The refineries are designed to produce low-sulfur fuels.

While plans for those projects were developed by Petrobras, as the state-owned oil company is known, they have been dropped from its investment plan. The source was not clear if any Iranian investment would include Petrobras.

Battered by financial problems, a corruption scandal and falling oil prices, Petrobras suspended work on both projects. Each is expected to cost more than $15 billion.

To help reduce its debt of abut $130 billion, Petrobras plans to sell $15.1 billion of assets by the end of this year and it has long said it has been seeking partners for its refinery assets.

Earlier on Thursday, Brazilian Mines and Energy Minister Eduardo Braga said Brazil "is in talks with the Iranians about the question of refineries in Brazil" but he declined to give details.

Petrobras declined to comment on the possibility of Iranian investment in Brazilian refineries.

(Reporting by Leonardo Goy, writing by Jeb Blount in Rio de Janeiro; Editing by Dan Grebler and Cynthia Osterman) ((Jeb.Blount@thomsonreuters.com; +55-21-2223-7143; Reuters Messaging: jeb.blount.thomsonreuters.com@reuters.net))

Keywords: BRAZIL IRAN/REFINERIES