Human rights organizations, including Amnesty International, have long criticized Iran for carrying out one of the highest numbers of executions globally.
Both sides emphasized the need for additional time to enable refugees to move their belongings and return voluntarily and with dignity.
The sharp rise in detentions and deportations has sparked renewed criticism from rights advocates inside Iran.
The proposal was made during a high-level meeting in Tehran between Iranian Interior Minister and the UN High Commissioner for Refugees.
The killing has sparked widespread outrage on social media and renewed concerns over violence targeting Afghan migrants in Iran.
The UNHCR also voiced alarm at the scale and speed of returns. Babar Baloch, spokesperson for the agency, said more than 50,000 Afghans crossed back from...
Migrants are being pulled off the streets without notice, loaded onto buses, and abandoned at the Afghan border, Khalilzad said.