Former German chancellor Angela Merkel has been awarded the 2022 Unesco Peace Prize for "her efforts to welcome refugees".

"All the members of the jury were touched by her courageous decision in 2015 to welcome more than 1.2 million refugees, notably from Syria, Iraq, Afghanistan and Eritrea. This is the legacy she leaves," jury president and 2018 Nobel Peace Prize winner Denis Mukwege said on Tuesday.

The director general of the UN cultural organization, Audrey Azoulay, also praised Merkel, saying her win serves as a reminder "that the way in which we treat migrants and refugees is a critical issue", reports dpa news agency.

The honour, which is officially called Felix Houphouet-Boigny-Unesco Peace Prize, is named after the former president of Ivory Coast.

It has been awarded each year since 1989 to individuals, organisations or institutions that have made a special effort to promote, research or secure peace.

It has not yet been decided when the prize will be handed over to Merkel, who left politics last year after serving four terms as Chancellor.

In the summer of 2015, as refugees were streaming into Europe, Merkel opened her country's borders and famously declared to Germans "Wir schaffen das", "We can do this."

She eventually pulled back on her pro-immigration stance as support eroded among the public and within her own conservative party.