By Julia Fioretti BRUSSELS (Reuters) – European Union countries need stricter controls to protect citizens from spying, a top data protection official said on Thursday, a warning that may rekindle a debate about snooping before an EU summit next week. Revelations by former U.S. intelligence contractor Edward Snowden about mass surveillance of global Internet traffic and phone records have prompted calls in Europe for tighter safeguards and a review of data-sharing agreements with the United States, but so far with few concrete results. In a letter to European Council President Herman Van Rompuy, data protection official Peter Hustinx expressed concern that EU heads of state might fail to make a strong enough commitment to protect their citizens.