Luxembourg ? Iran’s foreign minister on Tuesday warned Britain, France and Germany that they must make more economic and technological concessions to meet a deadline next month for agreement on Tehran’s nuclear activities.

The three European Union powers are trying to persuade Iran to abandon its uranium enrichment program, which Washington fears could be used to manufacture nuclear weapons. Iran insisted again Tuesday that its nuclear activities are peaceful.

But the talks still need much progress to reach a fruitful conclusion, Iranian Foreign Minister Kamel Kharrazi said after discussions with the Luxembourg government, which holds the EU presidency.

“It needs more efforts, more seriousness, more confidence building to be evaluated as a fruitful and positive process,” he added. “So we have to try harder and be more serious.”

Kharrazi called for the 25-nation bloc to be more open on economic and political issues.

Iran suspended its uranium enrichment program last year and it plans to decide soon whether to continue the suspension, which is monitored by U.N. nuclear inspectors.

Iran’s top nuclear negotiator, Hasan Rowhani, said earlier this month that his nation would not be obliged to continue talks if no progress is made by March 20, which would mark the end of the Iranian calendar year.

In exchange for nuclear guarantees, the Europeans are offering Iran technological and financial support and talks on a trade deal.

Kharrazi will be at the EU headquarters in Brussels, Belgium, for more talks today.