He served as foreign minister until 1980, acquiring a reputation as an effective, well-connected and hardworking minister, although he was seen by some as an international playboy, particularly through his well-publicised relationship with Shirley MacLaine (his marriage had by this time ended in divorce). He had a number of acrimonious disputes with Fraser, particularly over the recognition of the Khmer Rouge regime in Cambodia. After the 1980 election he asked for a change of portfolio, and Fraser made him Minister for Industrial Relations. He also challenged for the deputy leadership against incumbent Phillip Lynch, but was defeated 47 votes to 35. In April 1981 he suddenly resigned, accusing Fraser of constant interference in his portfolio. Fraser called a party meeting, at which Peacock tried to depose him as party leader and prime minister. Fraser managed to fend off this challenge. John Howard succeeded Sir Phillip Lynch as deputy leader in the same meeting.