The federal government will review that figure as more information about the devastation unfolds and more money may be contributed, Foreign Affairs Minister Alexander Downersaid Monday.
The government had reports of six Australians so far missing in the region hit by the waves, but Downersaid there were fears were held for nationals vacationing in Sri Lanka, particularly the resorts region of Galle.
"This would simply be the continuation of a ballistic missile early warning partnership we have shared with the U.S. over 30 years, a partnership which makes a significant contribution to global strategic stability, " said a spokeswoman for Foreign Minister Alexander Downer.