Iranian nuclear negotiators should not yield to pressures by the other party in ongoing nuclear talks, Iran's Supreme Leader Ayatollah Ali Khamenei said on Wednesday.

"The negotiators should not accept any forceful rhetoric from the other side, and Iran-IAEA relations should be ordinary," Khamenei said implying that the Iranian negotiating team should not undertake any extra obligations vis-a-vis the UN nuclear watchdog.

"Iran will neither give up nor slow down nuclear research and development activities as it continues its nuclear talks with the world powers," he stressed.

"The Islamic republic will not halt any of its nuclear achievements either," he added.

The remarks by the Iranian supreme leader comes as Iran and the P5+1 group, namely Britain, China, France, Russia, United States plus Germany, started their second day of talks in Vienna on Wednesday in an attempt to pave the ground for a comprehensive deal which might put an end to a decade-long standoff in the country's nuclear issue.