(Adds quotes, details, background)
BEIRUT, Jan 2 (Reuters) - Lebanon's Shi'ite Hezbollah condemned the execution of a prominent Shi'ite cleric in Saudi Arabia on Saturday, calling it an "assassination" and blaming it on the United States and its allies' support for Riyadh.
Sheikh Nimr al-Nimr and three other members of Saudi Arabia's Shi'ite minority were executed on Saturday alongside 43 Sunni jihadists, drawing condemnation by Shi'ites across the Middle East
The "real reason" for the execution was "that Sheikh Nimr... demanded the squandered rights of an oppressed people," Hezbollah said in a statement, apparently referring to Saudi Arabia's Shi'ite minority.
"The Saudi authorities ... put them (the Shi'ites executed) together with terrorist bands and groups which had committed crimes against civilians. Sheikh Nimr resisted oppression with words," the Hezbollah statement said.
It said it held the United States and its allies directly responsible through their support for the Saudi government, and urged the international community and rights groups to condemn the execution.
Lebanon's Supreme Islamic Shi'ite Council earlier said Nimr's execution was a "grave mistake... and an execution of reason, moderation and dialogue."
Nimr, who had called for pro-democracy demonstrations, was arrested in 2012, spurring protests in which three died. He had long been regarded as the most vocal Shi'ite leader in the eastern district of Qatif, willing to publicly criticise the Al Saud ruling family and call directly for elections. But he was careful to avoid calling for violence, analysts say.
Saturday's executions took place in 12 cities in Saudi Arabia, four prisons using firing squads and the others beheading.
The simultaneous execution of 47 people - 45 Saudis, one Egytian and a man from Chad - was the biggest mass execution for security offences in Saudi Arabia since the 1980 killing of 63 jihadist rebels who seized Mecca's Grand Mosque in 1979.
(Reporting by John Davison; Editing by Catherine Evans, Larry King)
Our Standards: The Thomson Reuters Trust Principles.