The EU's foreign policy chief says more sanctions against Syria and Iran are being weighed.

Catherine Ashton said Saturday that a top priority for the EU is to offer its full backing to the new U.N.-Arab League envoy to Syria, Lakhdar Brahimi, who is set to begin mediation efforts to end the violence between Syrian President Bashar Assad's regime and opposition groups seeking to topple his rule.

Speaking to reporters at the end of an EU foreign ministers meeting in Cyprus, she urged Syrian opposition groups to form a united front against the Assad regime in order to make all Syrians feel secure about their future.

On Iran, Ashton said that she will "do everything I can" to ensure Iran complies with its obligations regarding its nuclear program.