US President Barack Obama said Monday that unemployment and economic growth remain enormous challenges for Spain and other European countries. Obama spoke with reporters in the Oval Office of the White House after meeting with Spanish Prime Minister Mariano Rajoy. Obama said that the United States is more optimistic about Europeâ€™s prospects than a year ago. The U.S. president praised the difficult structural reforms Spain has undertaken as necessary precursors to growth. He said that those steps are never the most politically popular, but they are necessary. â€œI congratulated the prime minister on the progress thatâ€™s been made in stabilizing the economy, moving into growth, reducing the deficit, and being able to return to the financial markets in a way that reflects sound leadership,â€ Obama said.