Calls are mounting for Silvio Berlusconi's top political aide to resign as interior minister over the botched deportation of the wife and 6-year-old daughter of a businessman who is a foe of Kazakhstan's government.

Minister Angelino Alfano has insisted he knew nothing about Kazakhstan's diplomats urging lower-level ministry officials to deport Mukhtar Ablyazov's family from their Rome home in May.

Alfano says he will brief the Senate about it Tuesday, a few hours after his ministry cabinet chief resigned in the flap.

Premier Enrico Letta has told Parliament the deportations shouldn't have been ordered. The woman and child were spirited to Kazakhstan on an Italian government jet.

Any Alfano resignation could threaten the survival of the three-month-old government, a tense coalition depending on Berlusconi's support. Ablyazov's whereabouts are unknown.