A renowned German psychiatrist has described German Chancellor Angela Merkel's "stubbornness'' on pursuing her migration policy despite mounting public opposition as a sign of "mental breakdown.''

Speaking to Huffington Post Germany, Dr. Hans-Joachim Maaz said Merkel's determination not to admit that she was wrong about her migration policy made her "lost touch with reality,'' which he said could be dangerous for the country.

He said Merkel is suffering from "narcissism" brought on by people praising her as ''mother of the nation,'' most powerful woman in the world, and a leader deserving of the Nobel Peace Prize. He said the "artificially inflated self-image" she nurtures leads to her "stubborn attitude" as shown during the ongoing migrant crisis, Breitbart reported.

Maaz described the German leader as a typical overachiever who often goes to great lengths to please others in order to get validation of her own worth from others since her own self esteem is low. He said Merkel also "reacts to situations rather than leads," something which testifies to her lack of self-worth.

"If she continues to follow the behavioural patterns of the classic overachiever, a psychological or psychosomatic collapse is imminent,'' he told the paper.

The German Chancellor is being heavily criticised over her ''open border'' policy that resulted in 1.1million refugees and migrants entering Germany last year.

Maaz said Merkel's decision to open Germany's border was an "emotional" one, adding that the praises she has been receiving worldwide for her humanitarian act have fed her narcissism.

The unprecedented number of migrants and refugees who entered the country last year was described as an act of historic generosity towards refugees. While many of the refugees came from war-torn countries like Syria, the others were from countries with no valid claim for asylum.

"All refugees from the civil war in Syria would be welcome, regardless of where or how they entered the EU,'' Merkel previously said, noting that Germany was a rich country that could afford to do its part to take in some of the world's most vulnerable people fleeing war. ''If Europe fails on the question of refugees ... then it won't be the Europe we wish for.''

But the humanitarian act is not being well received by many Germans who feel that the entry of asylum seekers carries potential terror risks.