The government in Thuringia, central Germany, will approve loan guarantees worth €27.9 million ($34 million) for Opel, the Süddeutsche Zeitung newspaper reported.
In North Rhine-Westphalia, western Germany, officials are set to grant €100 million in guarantees and a similar decision is expected in Rhineland-Palatinate, Handelsblatt added.
In Hesse, western Germany, where Opel's headquarters are located, authorities are more reserved, the paper reported.
Opel unveiled on Friday an agreement with workers on a restructuring plan and said the carmaker had also found banks willing to lend it money if reimbursement were guaranteed by the government.
At the level of national authorities however, "no final decision has been taken," German Economy Minister Rainer Brüderle said in Brussels.
A commission of economists must submit a non-binding opinion on aid to Opel, which has asked for more than €1 billion in loan guarantees from the federal and state governments.
Brüderle said the commission would meet in the coming days, and Nick Reilly, head of GM Europe told Handelsblatt he was optimistic German politicians would in the end grant approval for the aid.