"The (Iranian) mullahs and their regime are not only a threat to the Iranian people but to all humanity," Rajavi said according to Norwegian news agency NTB.
Solberg said Norway was concerned with "the human rights situation and developments in Iran."
Marit Nybakk of the Labour Party, the main party in Norway’s ruling red-green coalition, said it was "important to meet everyone who is in opposition to the Iranian regime."
Nybakk added that talking with Iranian regime opponents was not the same as supporting them, and noted that the United Nations has not listed Rajavi’s group as terrorists.
The exiled leader also met with deputy speaker Carl I Hagen of the populist Progressive Party that has favoured ties with the NCRI.
Iranian diplomats have protested against the meeting.
A similar meeting in Brussels between Belgian senators and Rajavi last month also sparked criticism from Tehran.
The NCRI is a umbrella group of Iranian opposition groups, including the armed People’s Mujaheddin.