Archbishop Emeritus Desmond Tutu on Thursday afternoon broke his "vow to remain silent on public affairs" to call on Myanmar de facto leader Aung San Suu Kyi to speak out about the Rohingya crisis.
An estimated 125 000 Rohingya Muslims, roughly 4% of Myanmar's population, have been forced to flee to Bangladesh since military operations were launched in the northern parts of Rakhine in the middle of August to find militants who allegedly raided police border posts, AFP reported.
In a letter address to Suu Kyi, Tutu said it is not fitting for a "symbol of righteousness" such as Suu Kyi to lead a country where this kind of atrocity occurs.
"My dear sister: If the political price of your ascension to the highest office in Myanmar is your silence, the price is surely too steep," Tutu said.
"A country that is not at peace with itself, that fails to acknowledge and protect the dignity and worth of all its people, is not a free country."
Tutu said when Suu Kyi was released from house arrest in 2012, he believed it would bring relief to the persecution of Rohingya Muslims in Rakhine.
"But what some have called 'ethnic cleansing' and others 'a slow genocide' has persisted - and recently accelerated. The images we are seeing of the suffering of the Rohingya fill us with pain and dread.
"As we witness the unfolding horror we pray for you to be courageous and resilient again... We pray for you to intervene in the escalating crisis and guide your people back towards the path of righteousness."
Suu Kyi, who was awarded the Nobel peace prize in 1991, has recently been criticised for her lacklustre response to the ongoing crisis.
Myanmar's constitution doesn't allow direct government control of the military with the military having final say over constitutional amendments.
In a Facebook post on Myanmar State Counsellor Office on September 5, Suu Kyi said the discrimination of Rohingya Muslims was distorted through misinformation.
She pointed towards fake images shared by a Turkish Minister which were "photographs taken elsewhere in the world and not in Burma".
In April, Suu Kyi told the BBC "ethnic cleansing is too strong an expression to use" for the Rohingya crisis.
She said there was "a lot of hostility" in the western state of Rakhine, where most of the Rohingya Muslims live.
"It is not just a matter of ethnic cleansing. It is a matter of people on different sides of a divide, and this divide we are trying to close up. As best as possible and not to widen it further.
"It is Muslims killing Muslims, as well."
Myanmar's constitution bars Suu Kyi from becoming the President in Myanmar because her sons are British, but she previously vowed to rule from "above".
Shortly after elections in 2015, Suu Kyi assumed the newly created role of State Counsellor which many have come to see as the de facto leadership position.
A UN investigation into the human rights violations of the Rohingya Muslims was launched in March.
In April, Myanmar appointed former UN chief Kofi Annan to lead its own probe into possible crimes in Rakhine.