Kerry Says May Meet Iran's Zarif Again This Week

US Secretary of State John Kerry speaks during a press conference at the Council of Ministers building during a visit to Sofia, Bulgaria, Jan. 15, 2015.

U.S. Secretary of State John Kerry said Thursday that he might meet Iran's foreign minister again this week to discuss Tehran's nuclear program following their roughly six hours of talks Wednesday.

Iran and six world powers have renewed their quest for an elusive nuclear deal — seen as crucial to reducing the risk of a wider Middle East war — after negotiators failed for the second time in November to meet a self-imposed deadline. The talks between Iran and the P5+1 nations — Britain, China, France, Germany, Russia and the United States — are to resume Sunday in Geneva.

The major powers hope to persuade Iran to curb its nuclear program, which the West suspects may seek to develop atomic weapons, in exchange for a gradual easing of economic sanctions. Iran says its nuclear program is solely for peaceful purposes.

German Foreign Minister Frank-Walter Steinmeier said Thursday that nuclear talks with Iran were in a "decisive phase" and that no more time could be wasted. He said extensions to a temporary agreement could not continue indefinitely.

Kerry and Iranian Foreign Minister Mohammad Jawad Zarif met for about six hours in Geneva on Wednesday.

“There is no final decision as to whether or not we will meet in Paris,” Kerry told reporters in the Bulgarian capital, Sofia, noting he and Zarif would both be in the French capital on Friday.

Kerry sidestepped a question about whether it was possible for the United States to strike a nuclear deal while Iran continues to detain a number of U.S. citizens, saying only that Washington was making great efforts to secure their release.