EU High Representative Catherine Ashton arrived in Tehran on Saturday, her first visit, heading a high level delegation where she will meet with high ranking Iranian officials.Ashton visit comes in response to an invitation by Iranian Foreign Minister Mohammad Jawad Zarif to discuss Iran's nuclear program and relations between the Iran and the European Union.Ashton is also expected to meet Iranian President Hassan Rohani and Parliament Speaker Ali Larijani.Her visit to Tehran comes a week before the next round of negotiations between Iran and the P5+1 group on March 17th in Vienna.