The World Health Organisation (WHO) says that nearly one billion people worldwide suffer from some form of mental disorder, according to the latest UN data.
The data released says the staggering figure was even more worrying because it included around one in seven teenagers.
It said in its largest review of mental health since the turn of the century, that WHO had urged more countries to get to grips with worsening conditions.
According to the data, social and economic inequalities, public health emergencies, war, and the climate crisis are among the global, structural threats to mental health.
It says that depression and anxiety went up by more than 25 per cent in the first year of the pandemic alone.
Ghebreyesus said that even before COVID-19 hit, only a small fraction of people in need of help had access to effective, affordable and quality mental health treatment, citing the latest available global data from 2019.
He said, for instance, more than 70 per cent of those suffering from psychosis worldwide did not get the help they needed.