Mediation between sacked climate scientist Jim Salinger and the state science company which employed him failed to reach an agreement today, his lawyer said.

Dr Salinger was sacked from the National Institute of Water and Atmospheric Research (Niwa) last month after more than 20 years service.

The high-profile scientist, whose work contributed to a Nobel prize, was reported to have been axed for ignoring a new Niwa policy against speaking publicly without prior approval.

His dismissal sparked an outcry and criticism of Niwa.

The Institute of Agricultural and Horticultural Science said that the sacking was an "extreme embarrassment" for the country.

After the two sides met at a closed mediation session in Auckland today, Dr Salinger's lawyer Alex Hope said that no agreement had been reached but negotiations would continue.

He said a range of outcomes was possible.

"Either he gets his job back on reasonable terms, or if they are not prepared to reinstate him, does he get adequate compensation? If mediation is not successful then we will go to the Employment Relations Authority to resolve those issues."