Zarif met Monday in Munich with German Foreign Minister Frank-Walter Steinmeier on the sidelines of a multilateral security conference.
The Iranian minister said he was optimistic a final deal on nuclear issues could be made by the end of the year, provided all sides approached the issue in good faith, Iran's semiofficial Fars News Agency reported.
"With good will, we can reach an agreement within six months," he was quoted as saying.
Iran, under the terms of a November agreement with the P5+1 group of six world powers, agreed to suspend nuclear enrichment activity in exchange for relief from some economic sanctions.
Germany is a member of the P5+1, a nuclear negotiating body that includes representatives from the United States, Russia, China, United Kingdom and France.
Another round of talks between Iran and the P5+1 is scheduled Feb. 18 in Vienna.
Iran is suspected of pursuing the technology to make a nuclear weapon, an allegation it denies.
Iran agreed to give U.N. nuclear inspectors greater access to its nuclear research programs under the terms of a separate deal with the International Atomic Energy Agency.