Afterwards, the era of constitutional monarchy gradually came to an end as the Shah increasingly exercised his executive powers unilaterally, thus leading towards the development of autocracy. By the early 1970s, with most political parties having been banned, Iran had effectively become a one-party state under Rastakhiz. National Front leaders like Karim Sanjabi and moderate traditional Islamic leaders like Mohammad Kazem Shariatmadari continued to espouse a constitutional monarchy.