Washington, Oct 2 (DPA) US President Barack Obama said initial talks with Iran Thursday were “constructive” but cautioned Tehran must take concrete steps to assure the world its nuclear activities were peaceful and that US patience was “not unlimited”.

Obama made the remarks hours after talks led by EU (European Union) foreign policy chief Javier Solana with Iran and included representatives from Britain, China, France, Germany, Russia and the US concluded in Geneva.

“Today’s meeting was constructive but it must be followed with constructive action by the Iranian government,” Obama said.

The US official at the meeting, Undersecretary of State William Burns, met separately with Iranian negotiator Saeid Jalili, marking the highest level contact between the two countries in 30 years.