Opposition politicians including Left party chairman Bernd Riexinger and former leading candidate for the Green Party, Juergen Trittin, have demanded that the government grant Snowden asylum in return for his testimony on US spying that included alleged monitoring of Merkel's mobile phone.
German Interior Minister Hans-Peter Friedrich also said last week that the government was willing to talk with Snowden on the US spying if he was willing to shed light on the spying scandal.
American allies in Europe have been in an uproar over media reports that US intelligence agencies have monitored tens of millions of phone calls on the continent.
Snowden provided classified documents with evidence of the alleged spying scandal. He has been granted temporary asylum in Russia after exposing massive surveillance by the US intelligence service.
