Prime Minister Whitlam and Lance Barnard as a cabinet of two, for example, announced Australia's recognition of China and Papua New Guinea's independence before parliament met after the 1972 election. But cabinet itself is subject to its own pressures and constraints. The prime minister can have a lot of say over foreign policy. One of the reasons is the fact that the prime minister is the principal spokesperson for the country. Prime ministers meet and talk with other heads of state when negotiations are carried on between governments.
Modern communications make it easier for leaders to meet at the personal level more frequently.
Prime Ministers attend summits and international conferences and must be able to negotiate on behalf of the country. The extent to which a prime minster gets involved may depend on the interest and personality of the PM in office. Whitlam and Fraser were intensely interested. Hawke did not take such an active role in policy but he still took his photo-opportunities with the great and powerful friends. Howard seems to leave it more to Alexander Downer, but undertakes the occasional overseas visit.