Among other things, the girl has been accused of prostitution.
Norway has sent a formal protest to Iran about the matter.
A representative from the Iranian embassy in Oslo was on Monday summoned to the Foreign Office to receive the Norwegian protest.
Petersen says the planned execution is totally unacceptable.
The development for human rights in Iran gives grounds for deep concern, the Norwegian Foreign Minister says.
Norway also endorses a protest note from the EU, and has made this clear to the Iranian embassy.
On Monday there was also a protest demonstration outside the Iranian embassy, and the leader of Amnesty International Norway, Petter Eide, attempted to hand over a protest list with thousands of signatures to the embassy, but was not accepted.
