Sri Lanka has coordinated the rescue of 40 Iranian sailors from 19 commercial ships in international waters off its coast, its foreign ministry said.
The sailors were brought ashore at the Galle Harbour on the southern coast and given medical treatment before being returned to Iran early on Sunday morning, ministry spokesman Thushara Rodrigo said.
The ministry received a request from the Iranian embassy through diplomatic channels. Mr Rodrigo said they had been suffering unspecified medical emergencies. The ministry gave no further details of why they needed rescuing.
"This does not mean that we will provide assistance to those ships," he told BBC Sinhala. "It is generally an internationally accepted tradition to respond to a distress call after receiving it."
Mr Rodrigo said Sri Lanka was obliged under international law and on humanitarian grounds to provide the necessary facilities for medical emergencies, and that several agencies, including local shipping companies, were involved.
The sailors were on US-sanctioned oil tankers, local media reported.
Washington has imposed a blockade on Iranian shipping as part of its war on Iran.
Sri Lanka's navy and coastguard typically provide support during humanitarian efforts, a government source with direct knowledge of the rescue told Reuters.
It is the second time this year that Sri Lanka has rescued Iranian sailors. In March, it rescued dozens of crew after the Iranian warship IRIS Dena was sunk by a torpedo from a US submarine on 4 March.
The bodies of more than 80 sailors who died in the attack were flown back to Iran in mid-March, and 32 survivors of the sunken ship, along with 208 crew members from another vessel, were returned to Iran in April, Reuters reported.
The rescue comes as the blockade remains at the centre of efforts to end the standoff.
Iran's ambassador to Pakistan, Reza Amiri Moghadam, said at a seminar in Islamabad that Tehran had told Pakistani mediators it was prepared to reopen the Strait of Hormuz if Washington ended its blockade of Iranian ports. Iran has accused US president Donald Trump of rejecting the proposal by insisting the blockade would continue, AP reported.
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