German Foreign Minister Guido Westerwelle expressed caution Tuesday in response to an offer by Iranian President Mahmoud Ahmadinejad to enter negotiations on the country's nuclear ambitionsç dpa reported
Westerwelle said the offer showed "that the unanimous stance of the European Union is working and that we are ... consistently following the correct policy."
However he added that partial offers were not the right solution, and called for "absolute transparency over the nuclear programme."
The German foreign minister was addressing journalists in the Slovenian capital Ljubljana on Tuesday, before travelling on to the Turkish city of Istanbul.
EU foreign ministers on Monday approved a list of sanctions which go well beyond measures previously approved by the United Nations.
In response, Ahmadinejad reiterated his willingness to resume nuclear talks with the world powers after the Muslim fasting month of Ramadan, which ends early September.
Rather than increase sanctions against Iran, Turkey has pursued a separate approach with Brazil, aimed at brokering negotiations with Tehran.
"A nuclear armed Iran would be a serious threat, not just for the region but for the entire security structure of the world," Westerwelle said, adding that the EU sanctions demonstrated a consolidated approach.
Westerwelle said Turkey, his next port of call, was pursuing the same goals as the EU with regard to Iran's nuclear programme, and refused to draw connections between the Turkey's diplomatic efforts over Iran and its ambitions to join the EU.
"A process without a foregone conclusion has been set in motion. And that will be processed factually and fairly, faithful to the treaties and laws," Westerwelle said of Turkey's EU accession talks.
The German foreign minister is expected to discuss Iran's nuclear ambitions with his Turkish counterpart Ahmet Davutoglu in Istanbul later on Tuesday