BUENOS AIRES - Brazilian Finance Minister Fernando Haddad played down the idea of a single shared currency between Argentina and Brazil late on Sunday, saying the countries were looking at ways to stimulate bilateral trade but not extinguish their own currencies.

His remarks came after Brazilian President Luiz Inacio Lula da Silva and Argentine leader Alberto Fernandez published a joint article saying their aim for greater economic integration included studies of a common South American currency.

Haddad, who floated such a possibility in an article last year, said removing trade barriers between the two largest economies in South America could involve using a single currency for commerce, given a lack of U.S. dollars in Argentina. But that does not spell the end of the Brazilian real, he said.

"Trade is really bad and the problem is precisely the foreign currency, right? So we are trying to find a solution, something in common that could make commerce grow," Haddad told reporters as he arrived in Buenos Aires ahead of Lula's first international trip since his Jan. 1 inauguration.

He said Argentina's trade with Brazil had suffered due to a lack of dollars in the southern neighbor, where an economic crisis has left the government battling to replenish foreign currency reserves, with an inflation rate of nearly 100% last year.

Haddad noted Argentina was an important buyer of Brazilian industrial goods and that "several possibilities" were being floated to circumvent its currency problems, though no decision had been made.

Asked if he could provide further details on the currency issue, Haddad confirmed he would clear the matter up in coming days, adding ironically: "especially because some people are saying the real will end."

Earlier on Sunday, Lula and Fernandez said in an article published on the Argentine website Perfil they would "advance discussions on a common South American currency that can be used for both financial and commercial flows".

The Financial Times had previously reported, citing Argentina's Economy Minister Sergio Massa, that the neighboring nations would announce this week they were starting preparatory work on a common currency.

(Reporting by Lisandra Paraguassu; Writing by Gabriel Araujo; Editing by Brad Haynes and Bernadette Baum)