He said: "We had a friendly and frank exchange of views about enhanced cooperation between Iran and the International Atomic Energy Agency (IAEA) and how to clarify the outstanding issues".
ElBaradei's comments came after talks with Gholam Reza Aghazadeh, the head of Iran's Atomic Energy Organisation (IAEO) on Friday.
"I discussed with Mr Aghazadeh how we can work together and accelerate the pace of our cooperation to clarify all outstanding issues before my report in March."
"I'm looking forward to an environment of accelerated cooperation."
Further talks
ElBaradei is due to meet other top Iranian officials, including Mahmoud Ahmadinejad, the president, Saeed Jalili, Iran's chief nuclear negotiator and supreme leader Ayatollah Ali Khamenei on the second day of his visit on Saturday.
Aghazadeh, who described the talks as "very good", pledged that Iran would continue with its cooperation with the agency.
He said: "We will continue our cooperation in all areas to solve the all problems. We are entering into a new phase and I think that the climate is right to solve all the problems.
"I advise the Westerners to profit from this climate."
Final conclusions
Despite a four-year investigation into Tehran's atomic drive, the IAEA has never been able to confirm whether the programme is peaceful.
The aim of its latest talks with Tehran is to finally draw this investigation to a conclusion.
Ahmad Khatami, a cleric, told worshippers in Tehran during Friday prayers: "We hope that ElBaradei, after seeing the reality, will make a positive and realistic report and close our case completely at the agency."
ElBaradei, who is accompanied by Olli Heinonen, the IAEA deputy director-general, is due to hold a news conference with Aghazadeh at 1230 GMT.
It is possible he will hold talks with supreme leader Ayatollah Ali Khamenei on Saturday.
Sanctions insisted
A recent US intelligence report said Iran halted a nuclear weapons programme in 2003, undermining repeated accusations from George Bush, the US president, that Tehran was actively seeking the atomic bomb.
The report appears to have momentarily taken the heat out of the crisis, but Washington still wants the UN Security Council to adopt a third set of sanctions against Tehran.
The UN Security Council has repeatedly called on Iran to freeze the process of uranium enrichment - which can be used both to make atomic fuel and a weapons.
But Iran has repeatedly said it has a right to the full nuclear fuel cycle and insists its nuclear programme is solely aimed at generating electricity for a population whose fossil fuels will eventually run out.