The European Union is studying a call by Iran to resume negotiations over the country's nuclear program but still insists it must suspend uranium processing, British Foreign Secretary Jack Straw said on Monday. "We have looked at the letter very carefully. The Iranians are under an obligation to respond positively to the resolution of the board of governors of the International Atomic Energy Agency ... and we look to them to do that," Straw told reporters before a meeting of EU foreign ministers. Separately, EU foreign policy chief Javier Solana added of the letter from Tehran received by EU officials on Sunday: "We will respond ... We don't want to go any further at this point."