TOKYO (Reuters) - Trade Minister Shoichi Nakagawa said on Monday that Japan must balance its oil needs against concerns over Iran's nuclear program in talks to develop Iran's Azadegan oilfield, but he sidestepped the issue of whether a deadline had been set for a decision. "We need to ensure our oil supply, but as the only country that has suffered from an atomic bombing, we cannot be unconcerned about nuclear weapons," Nakagawa told Reuters in an interview. "We must balance these in handling this issue."

An Iranian official said on November 29 that Tehran was weeks away from setting a deadline in bids for the $2 billion investment race for the southern part of Azadegan, one of the world's largest untapped oilfields.

A government-backed private Japanese consortium had exclusive rights to negotiate an agreement but backed off under U.S. pressure linked to concerns over the nuclear program and lost its rights in June.

A source close to the negotiations was quoted by the Financial Times on Monday as saying that Iran was putting pressure on the consortium to decide by December 15.

"If there has been some kind of timing set, I believe a decision will have to be made in line with that," Nakagawa said, when asked about the report.

"But we are not aware if that (December 15) is final or not." Resource-poor Japan has been caught between its desire to develop the oilfield and pressure from the United States, its main security ally, to back off.

Both Japanese and Iranian officials said last month that the Japanese consortium was still in the running for the project.

Iran stressed on Sunday that it was committed to signing an international agreement binding it to snap inspections of its nuclear facilities.