Three well-known moderate Saudi scholars are reportedly due to be executed at Ramadan's end after being charged with multiple 'terrorism' offences.

London-based news outlet Middle East Eye (MEE) has reported two government officials and one of the men's relatives had confirmed the trio would soon be sentenced to death.

Among the three Sunni scholars is Sheikh Salman al-Odah, who is internationally renowned for his progressive Islamic views on Sharia Law and homosexuality, and has been described as a "reformist" by the UN.

He was arrested in September 2017 after he tweeted a prayer calling for reconciliation between Saudi Arabia and Qatar.

Twitter 'm3takl_en'

His co-accused are Awad al-Qarni, who is a preacher, academic, and author, and Ali al-Omari, who is a popular broadcaster. They were also arrested in September 2017.

The three men are still awaiting trial at Riyadh's Criminal Special Court, but MEE has reported two Saudi government sources independently confirmed their execution had already been decided.

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"They will not wait to execute these men once the death sentence has been passed," one of the government officials told MEE.

The other government source said Saudi's execution of 37 activists on terrorism charges just last month was used as a "trial" to test how strong the international reaction would be ahead of the trio's sentences.

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“When they found out there was very little international reaction, particularly at the level of governments and heads of state, they decided to proceed with their plan to execute figures who were prominent,” he told MEE.

Between them, the three men have more than 16.7 million Twitter followers, giving them a large online platform for their moderate politics.

A year after his arrest, Odah was finally charged with 37 counts of terrorism in a closed hearing of Saudi's Special Criminal Court.

Two days before his own murder inside the Saudi consulate in Istanbul, Saudi journalist Jamal Khashoggi spoke out against the charges and Saudi ruler Crown Prince Mohammed bin Salman.

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“He will crush dissent at all cost. These charges must be publicised,” Khashoggi said.

“Odah will be executed not because he is an extremist. It’s because he is a moderate. That is why they consider him a threat.”

A UN panel of experts from the Human Rights Council called on Riyadh to stop arresting religious figures, journalists and activists in what it called a "worrying pattern" or arbitrary arrests.

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“Despite being elected as member of the Human Rights Council at the end of 2016, Saudi Arabia has continued its practice of silencing, arbitrarily arresting, detaining and persecuting human rights defenders and critics," the panel said.

The US State Department, Amnesty International, Human Rights Watch, and Reprieve have also condemned Saudi's detention of the three scholars.