Janan Musazai also said Kabul would close its embassy in Bulgaria at the same time.
He said that with an estimated 25,000-30,000 Afghan refugees in Greece at any one time over the last two years, it's estimated that about 50,000 Afghans enter Greece illegally each year.
Many are either caught, jailed, or find themselves stranded with no money and no papers.
Musazai said a government delegation late last year provided 650 passports to Afghans who wanted to return home, and persuaded the authorities to free 100 Afghans held in detention centers for illegal entry.
Ahmad Saidi, an Afghan government adviser on migration, told RFE/RL's Radio Free Afghanistan that as long as unemployment, as well as a lack of security and justice, continue to plague Afghanistan, people will be forced to flee the country.
with agency reports