Berlin himself visited Tehran in the late 1970's, during the dying years of the shah's regime.
He has also established an indirect dialogue with Israel and invited French and British Jewish leaders to visit Tehran.
Both sides denied a rift when Assad visited Tehran in February.
In December 2008, Correa visited Tehran and signed several agreements.
He visited Tehran two weeks ago and told Iranian political leaders that he would come to Iran's aid if it was attacked.
Davutoğlu visited Tehran in February 2010 with the aim to broker a deal on the issue of uranium enrichment.
She still visits Tehran each year.
He also visited Tehran.
Mr Straw's enthusiasm for the enterprise even led him to become the first British foreign secretary to visit Tehran since the Islamic Revolution.
Now her father returns to visit Tehran, and CNN cameras trail her to a family celebration for his 85th birthday.
