Foreign Ministry spokesman Sultan Ahmad Bahin said Kabul expects the Iranian government to refrain from forcing out refugees in big numbers.
UN officials say more than 25,000 Afghans have been sent back by Iranian authorities since April 21.
Meanwhile, U.S.-led coalition forces raided a suspected car bomb cell in Afghanistan's eastern Nangarhar Province early today.
The coalition said the ensuing gunbattle in the Bati Kot area left four militants and two female civilians dead.
But Afghan police said the dead were all civilians.
Hundreds of Afghans blocked a main road near the provincial capital, Jalalabad, in an angry protest.
"They are committing so many operations against us," said one protester. "We do not want them. We do not want this kind of life in the future. America is our enemy. America is our enemy! Karzai is our enemy! Karzai is our enemy!"
U.S. Major Chris Belcher said in a statement that the U.S. army is saddened at the loss of civilian life. He said it is "extremely unfortunate that militants put others' lives in danger by hiding among their families."
(compiled from agency reports)