Between 1956 and 1958, Sudanese nationalist leaders from both major parties sought to find solutions to the seemingly intractable problems of building a nation, developing the economy and creating a permanent constitution. Neither Ismail al-Azhari, leader of the Nationalist Unionist party and the first prime minister of the Sudan, nor his rival, Abdullah Khalil, the Umma party leader and successor to al-Azhari as prime minister, was able to overcome the weaknesses of the political system or to grapple with the country's problems. Parliamentary government was so discredited that Gen. Abboud, who formerly had remained studiously aloof from politics, led a "coup d'état" on 17 November 1958, to end, in his words, "the state of degeneration, chaos, and instability of the country." The Council of State and cabinet were dismissed, parliament and all political parties were declared dissolved, and the constitution was suspended.