Iranian diplomats called the climate of negotiation between Iran and P5+1 "positive" and "constructive" after they attended the first day of talks, ISNA reported.
The high-level talks began on Monday in Geneva during which the two sides discussed wide range of subjects, including nuclear issue.
Iran has already said that it does not negotiate on its nuclear rights.
The negotiating groups also agreed to put non-proliferation, disarmament and peaceful nuclear work into discussion during Tuesday talks.
The three items were included in Iran's package of proposals which was delivered to representatives of the five permanent members of the UN Security Council plus Germany two years ago.
Iranian top nuclear negotiator Saeed Jalili during the first day of dialogue condemned the West's crime against Iranian scientists particularly Majid Shahriari who was assassinated last Monday.
The meeting was attended by representatives of P5+1 and European Union Foreign Policy Chief Catherine Ashton.
Jalili also had separate meetings with delegates of Russia, China and Britain.