UNITED NATIONS (AFP) - German Foreign Minister Guido Westerwelle welcomed a "new tone" from Teheran during a meeting with his Iranian counterpart Mohammad Javad Zarif on Tuesday in New York, diplomats said.
Mr Westerwelle was later set to meet Iran's new President Hassan Rouhani, who has made diplomatic overtures in the nuclear standoff with the West.
"The words of the new president are encouraging," Germany's top diplomat told journalists ahead of the planned meeting on Tuesday evening.
But he insisted that Teheran must take concrete steps to prove its willingness to engage.
"We now have to explore if the new rhetorical flexibilities are really associated with substantial movement," he said.
Mr Westerwelle will participate in high-level talks on the suspect nuclear programme on Thursday, joining counterparts from the United States, Britain, China, France, Russia and Iran.
On Syria, Mr Westerwelle urged world leaders to make renewed efforts for a political process during their annual gathering in New York.
"There cannot be a military solution in Syria. Only a political solution can bring sustainable peace and stability," he said.
Mr Westerwelle is scheduled to address the UN General Assembly on Saturday in what will likely be his last major appearance as foreign minister.
After four years at the helm of Germany's diplomacy, Westerwelle is set to leave office following his party's crushing defeat in Sunday's parliamentary elections.
