The source said Monday that the ministry has proposed Dmitry Pankin - the current head of the department for international financial relations, state debt, and state financial assets - for the post. Earlier reports cited the ministry as saying Storchak would retain his position.
The pre-trial detention of Storchak, a key figure in Russia's foreign debt talks, was recently extended until April 9.
Finance Minister Alexei Kudrin, who earlier offered personal guarantees to secure Storchak's release, repeatedly complained that the official's absence has affected the ministry's talks, including on Libya's debt, and on the early payment of Russia's World Bank debt.
Storchak himself said in court that his arrest has cost Russia $1 million each day.
The deputy minister was arrested on November 15 last year and charged along with several businessmen with attempting to embezzle $43 million in state funds. The suspect faces five to ten years in prison if convicted. He has denied the charges.
In line with a recent government move giving ministries the right to appoint up to five deputy ministers, the Finance Ministry requested permission for a fifth minister.
Pankin, 51, a trained economist and Kudrin's deputy at the economics and finance department of the St. Petersburg mayor's office in 1992-94, is likely to take on all of Storchak's functions and is expected to join a Russian delegation to the World Economic Forum in Davos, Switzerland, on Wednesday.
Media reports said earlier that even if freed in April, Storchak was likely to be placed under an order not to leave the country, so would not be able to travel abroad for talks.
Observers suggested Storchak's career as a statesman and an international negotiator is likely to be over even if he is cleared of the charges. They predict his resignation and a job at a bank.
The case against the deputy of liberal economist Kudrin has triggered speculation about attacks on the Kremlin's liberal bloc and revealed divisions in the Prosecutor General's Office and its main investigative committee, which has pushed for Storchak's prosecution. Top prosecutors have rejected fresh charges against Storchak.
