Given the task definition and input, reply with output. In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Passage: It is widely believed that Saudi Arabia has been a major financier of Pakistan's own integrated atomic bomb project since 1974, a programme founded by former prime minister Zulfikar Ali Bhutto. In the 1980s, Chief Martial Law Administrator and President General Zia-ul-Haq paid a state visit to Saudi Arabia where he unofficially told the King that: "Our achievements are yours". This cooperation was allegedly furthered by socialist prime minister Benazir Bhutto in 1995. In 1998, the conservative Prime minister Nawaz Sharif informed Saudi Arabia confidentially before ordering the nuclear tests (see Chagai-I and Chagai-II) in the Weapon-testing labs-III (WTL) located in the Chagai remote site in Balochistan Province of Pakistan. In June 1998, the Prime Minister paid a farewell visit to King Fahd and publicly thanked the Saudi government for supporting the country after the tests. Shortly thereafter, Saudi Minister of Defense Prince Sultan went with Prime Minister Sharif on a tour of a classified institute, the Kahuta Research Laboratories (KRL), where leading scientist Abdul Qadeer Khan briefed the Prince and Prime Minister Sharif on nuclear physics and sensitive issues involving nuclear explosive devices.
Link Information: Zulfikar Ali Bhutto (; ; 5 January 1928 4 April 1979) was a Pakistani barrister and politician who served as the 9th Prime Minister of Pakistan from 1973 to 1977 Question: What years did Zulfikar Ali Bhutto serve as prime minister?
Answer: from 1973 to 1977