TUNIS, July 31 (Reuters) - The head of Tunisia"s biggest party, the moderate Islamist Ennahda, on Saturday postponed a meeting of its highest council after senior members called for his resignation over his handling of the political crisis, party sources said. Rached Ghannouchi, who is also parliament speaker, has played a critical role in Tunisia"s democratic crisis this week after quickly accusing President Kais Saied of a coup when he declared he was seizing executive authority. The moves have caused the biggest crisis in Tunisian politics since the 2011 revolution that introduced democracy, with no announcement by Saied of a new prime minister or roadmap to end the emergency period. read more Saied"s moves, which also included freezing parliament and dismissing the prime minister, have also thrown Ennahda into turmoil, leading to recriminations within the party over its strategy and leadership. The party has been the most consistently powerful in Tunisia since the revolution, playing a role in backing successive coalition governments and has lost support as the economy stagnated and public services declined. On Saturday Ghannouchi postponed a meeting of its Choura Council, the party"s highest internal authority, shortly before it was due to take place, three party sources said. Dozens of younger party members and some of its leaders including Samir Dilou, a parliament member, had called on Ghannouchi to resign, the sources said. Ghannouchi has led Ennahda for decades, including from exile in Britain before the revolution, after which he returned to a tumultuous welcome at Tunis airport. He stood for election for the first time in 2019, winning a parliament seat and becoming speaker. read more