The exiled Islamist group has called for demonstrations in the past. The first of these resulted in several hundred people turning out in Riyadh on 14 October in a rare rally calling for change.

The protest, mounted during the kingdom's inaugural human rights conference, resulted in the detention of 271 people, of whom 188 were freed and 83 remain in custody, according to the Ministry of Interior.

 “If circumstances permit, we are calling for an impressive demonstration in Mecca near the end of Ramadan,” the holy Muslim fasting month, expected to start Sunday or Monday, spokesman Saad Faqih told AFP by telephone.
  
Saudi police on Thursday arrested more than 70 demonstrators in a bid to halt fresh protests called by MIRA.
 

“The demonstrations will continue during Ramadan,”  Faqih said.

"Why don't Saudi citizens have to right to demonstrate, including in Mecca, like the Iranians?" asked Faqih, in reference to to traditional protests by Iranian pilgrims on the plain of Arafat near Mecca during the high-point of the Hajj, the annual Muslim pilgrimage.

The march will call for “the rights of Saudis to demonstrate to denounce injustice and corruption in the kingdom,” he added. 

"The only disagreement lies between those who believe in military overthrow and those who believe in forcing political change through peaceful means."

Dr Muhammad al-Massari

Conservative Saudi Arabia, home to Islam's holiest sites, strictly outlaws public demonstrations.

The protest calls will add to the pressure on Saudi Arabia's monarchy, already reeling from attacks against state and western interests. 

On Saturday evening a group denounced by the government as having ties with al-Qaida described as lies a claim by the Interior Minister that they had uncovered an arms and explosives cache.

In a statement on their website the "Mujahidin of the Arabian Peninsula" said the weapons, uncovered earlier this week, belonged to a notorious arms merchant.

"The statement by the Interior Minister is packed with lies", the groups said.

"The Mujahidin of the Arabian Peninsula, who have gained combat experience in various scenes of jihad have acquired the arms necessary to fight America everywhere in the world, in particular in the land of the two sanctuaries of Islam (Makka and Madina) which the Crusaders have used as a base for their campaigns against Afghanistan and Iraq."

Amnesty International urged the kingdom on Friday to immediately and unconditionally release all those held "solely for the non-violent expression of their conscientiously held beliefs".

Amnesty also said Um Saud, one of three women arrested with the protestors and held in al-Malaz prison in Riyadh, was reportedly beaten and ill-treated during her arrest.

Another London-based Saudi dissident Dr Muhammad al-Massari, of the Committee for the Defence of Legitimate Rights, said the protests were only the tip of the iceberg.

He said: "There is a revolutionary spirit in Saudi Arabia. I think the majority of the people are now so fed up with the regime that they see no alternative but to overthrow it.

"The only disagreement lies between those who believe in military overthrow and those who believe in forcing political change through peaceful means."