"In Australia with Foreign Minister [Julie] Bishop and Defense Minister [Marise] Payne, we'll be looking at ways in which we can more effectively counter the provocations that the North Koreans are making, find more effective ways of increasing pressure on them, to get them back on a constructive path of de-nuclearization," Matthews said.
Tillerson and US Defense Secretary James Mattis will be in Sydney, Australia, June 5-6.
Their visit to the region comes as tensions are increasing between Washington and Pyongyang over the latter's nuclear and ballistic missile tests.
North Korea conducted its most recent ballistic missile launch on Monday. During the test, the projectile reportedly flew some 280 miles before falling into Japan's exclusive economic zone in the Sea of Japan.