LONDON (AFP) - The euro climbed against the dollar on Thursday when a successful sale of Spanish bonds eased fears about the eurozone debt crisis, analysts said. The European single currency climbed to 1.2338 dollars from 1.2306 dollars late in New York on Wednesday. Against the Japanese unit, the dollar fell to 91.28 yen from 91.45 yen on Wednesday. Relief that Spain has again been able to raise funds on the open market is helping sentiment, said Jane Foley, analyst at online trading firm The Spanish Treasury successfully borrowed 3.479 billion euros (4.305 billion dollars) by selling bonds on Thursday but at higher rates as investors sought more reward for lending after recent debt scares. The auction went well, with Spain issuing close to the maximum of the range announced, said Chiara Cremonesi, fixed income strategist at UniCredit Research. Market sentiment has been affected by rumours concerning possible strains within the Spanish banking system and suggestions that Spain might need help amounting to 200-250 billion euros (246-307 billion dollars) from the EU. European Union and Spanish officials have strongly denied such suggestions. Europe cracked its whip on excessive state borrowing on Thursday, laying foundations for cross-border economic government with a fearful eye on gathering dark clouds over Spain. Leaders were using a European Union summit to widen their focus from public overspends and also target dangerously high private sector debt, a bigger problem with Spains banks than it ever was with bailed-out Greece. As Madrid auctions off a major tranche of its sovereign debt, diplomats said that agreement had been reached in advance to toughen sanctions for those who blow their budgets. The euro had plunged to a four-year dollar low point last week on the back of heightened concerns about the eurozone debt and deficit crisis, sinking below 1.19, but has recovered in recent days. Elsewhere on Thursday, the Swiss central bank kept its key interest rate unchanged in line with analysts expectations, as it raised its forecast for growth in the Swiss economy this year to about 2.0 percent. In London trading on Thursday, the euro was at 1.2338 dollars against 1.2306 dollars on Wednesday, at 112.62 yen (112.53), 0.8370 pounds (0.8353) and 1.3765 Swiss francs (1.3914). The dollar stood at 91.28 yen (91.45) and 1.1157 Swiss francs (1.1304). The pound was at 1.4740 dollars (1.4729). On the London Bullion Market, the price of gold fell to 1,231 dollars an ounce from 1,234.50 dollars an ounce on Wednesday.