Spanish Prime Minister Mariano Rajoy (L) poses next to Spanish Economy Minister Luis de Guindos during the inauguration of the Inter American Development Bank in Madrid July 6, 2012. Domestic banks that have backed Spain's debt auctions with heavy buying could be reaching a limit for absorbing sovereign bonds, say financial analysts and two market makers, undermining the country's efforts to stave off a full-blown bailout. REUTERS/Andrea Comas (SPAIN - Tags: BUSINESS POLITICS)