Mullah Krekar, whose real name is Najmuddin Faraj Ahmad, sent a letter from prison, which was obtained by Norway's ABC News.
"In Norway it would be appropriate to vote for AP [Labour], SV [Socialist Left] or Red," he wrote. "Muslims in Norway are not sufficiently powerful or numerous that they are able to form a party of their own. And we feel that Stoltenberg was not, like [former Prime Minister Kjell Magne] Bondevik, blindfolded by Bush."
"The strategy for the leftists and Muslims have much in common," he added.
The parties did not seem overly pleased to have received Krekar's backing.
"We would discourage anyone to listen to Krekars political considerations," the Socialist Left's party secretary Silje Schei Tveitdal told VG.
"He has no voting rights, and he's not going to get any," said the Labour Party's Pål Lønseth.
Per Sandberg, one of the most vehement anti-Islamic figures in the populist Progress Party said he believed Krekar was "voting for his own good".
"He knows that a vote for Labor is a vote that he will be able to stay in Norway," Sandberg wrote in an email to VG. "No coalition led by the Labour Party will ever forcibly eject him," Sandberg wrote in an e-mail to VG.