The US Pacific Tsunami Warning Centre on Wednesday cancelled its tsunami watch alert linked to the earthquakes off the coast of Indonesia.
It had previously included some 20 countries on that list, including Indonesia itself, Sri Lanka, Kenya and the Maldives.
In a statement, it said that “sea level readings now indicate that the threat has diminished or is over for most areas.”
Indonesian officials said earlier that three tsunamis hit off Sumatra Island, but the largest measured just 80 centimetres high.
The alarm was raised after a massive 8.6-magnitude earthquake struck some 431 kilometres from the Indonesian city of Banda Aceh. It was followed by a powerful, albeit slightly weaker aftershock.
The earthquakes triggered a series of alerts across the region and tremors were felt as far away as Singapore and Vietnam.
But there were no reports of any damage or casualties.