German Chancellor Angela Merkel pressed for a "solid answer" from Iran to an international package of incentives aimed at persuading the country to rein in its nuclear program.

Tehran has said that it will offer a "multifaceted response" on Tuesday to the package, drawn up by the U.N. Security Council's five permanent members and Germany, but insisted it won't suspend uranium enrichment altogether.

"We are still waiting for a solid answer from Iran," Merkel told a news conference Monday. "I still hope that it will be positive, although some signals have been very confused."

Iran has said the package is an "acceptable basis" for a compromise and that, while part of the package is convincing, there are ambiguities that needed to be clarified in talks.

It includes promises that the United States and Europe will provide civilian nuclear technology and that Washington will join direct talks with Iran.

Last month, the U.N. Security Council passed a resolution calling for Iran to suspend uranium enrichment by Aug. 31 or face the threat of economic and diplomatic sanctions.

Iran, which claims its atomic program has only the peaceful aim of using reactors to generate electricity, has rejected the resolution as "illegal," saying it has not violated any of its obligations under the Nuclear Non-Proliferation Treaty.

"Iran must see that ... we have made Iran a very good offer for its economic development, but that we also demand that some rules be kept to," Merkel said.