This seems to be related to the ongoing AWS issue:
9:06 AM PST We are investigating an issue with an external provider outside of our network, which may be impacting Internet connectivity between some customer networks and the AP-SOUTHEAST-2 Region. Connectivity to instances and services within the Region is not impacted by the event.
9:39 AM PST We are continuing to experience connectivity issues with an internet provider external to our network. This affects international connectivity from AP-SOUTHEAST-2 Region to internet destinations outside Australia. Connectivity within the AP-SOUTHEAST-2 or to internet destinations within Australia are not impacted at this time. We are continuing to work towards shifting traffic from the external provider to recover from the event.https://status.aws.amazon.com