MOSCOW (AFP) - A man who took four people hostage at a bank in central Moscow late on Wednesday (Aug 24) has surrendered to police, local authorities said.

Russian special forces were deployed to the Citibank branch, located just one kilometre away from the Kremlin, after reports that a man had seized four hostages - three bank employees and one customer.

Moscow police said they were able to negotiate the release of two of the bank staff shortly after 1700 GMT (1am on Thursday, Singapore time).

The two remaining hostages were released later, the police told RIA Novosti state-run news agency.

An unnamed source in law enforcement told Russian news agencies that the hostage taker was apparently drunk and had threatened to blow up the bank.

Police told RIA Novosti state news agency that the hostage taker had an "unidentified object" attached to his neck.

The alleged hostage taker apparently posted a video online in which he claimed that the siege was intended to draw attention to corporate and personal bankruptcy in Russia, Interfax news agency reported.

"Why am I doing this?" a man said in a video uploaded to YouTube on Wednesday, the source of which could not be independently verified.

"Because there is no other way for you, for the general public to see that there is a huge problem in Russia," he added, referring to bankruptcy.

"I have nothing to lose. I have already lost everything that I had."

The man also demanded that authorities recognise bankruptcy as a "disease" and tackle the issue.

The Kremlin's business ombudsman Boris Titov said in an interview with a local radio station that he would assess the hostage taker's demands, RIA Novosti reported.

The Russian economy has been battered by a recession caused by low oil prices and Western sanctions over the Ukraine crisis.