BERLIN, Jan 19 (Reuters) - Former German chancellor AngelaMerkel has turned down the offer of a job at the United Nations,her office said on Wednesday, a month after she stepped down asEurope's most powerful politician after 16 years at the helm.

Merkel, 67, called U.N. Secretary General Antonio Guterreslast week to thank him for the job he had offered her in aletter and to tell him she would not accept it, the office said,without elaborating.

German media reported that Guterres had offered Merkel thechair of a high-level U.N. advisory body on global public goods,one of his flagship reform projects. It will focus on issuesincluding the ozone layer, vaccines and outer space debris.

Merkel, a conservative, has stayed out of the politicalspotlight since handing over Germany's chancellorship to OlafScholz, a Social Democrat.

She is working on a political memoir with her long-timeaide, according to an interview in Der Spiegel, but little moreis known about Merkel's life in retirement.

(Reporting by Miranda Murray and Andreas RinkeEditing by Gareth Jones) ((;))