The Indonesian navy prevented a suspected migrant boat from entering the country's waters over the weekend after the arrival of hundreds of Rohingya and Bangladeshis and has stepped up patrols in the area, the military said on Monday.

Nearly 3,000 migrants have swum to shore or been rescued off Indonesia, Malaysia and Thailand over the past week, around half of whom have arrived in Indonesia's western province of Aceh.

The three nations have sparked outrage by turning away some overloaded vessels, and thousands of migrants are still believed to be stranded at sea after a Thai crackdown disrupted long-established people-smuggling routes.