Brasilia, July 12 (AFP) - Claudio Loser, Western Hemisphere director for the International Monetary Fund, said he thinks a default by Argentina on its U.S. $128 billion foreign debt is unlikely. Draconian austerity measures hurriedly unveiled by the cash-strapped Argentine government failed to allay concerns that the government could default on its $130 billion debt, keeping downward pressure on other Latin American markets.