Police stopped the head of Argentina's central bank from entering the bank on Sunday, hours after he vowed to stay in his job despite a court ruling that the government said meant he had to step down.

Martin Redrado, who is locked in dispute with the president over her plan to use central bank reserves to pay debt, said he went to the bank with his lawyers to see if he would be allowed to enter the premises but that police officers stopped them.

(This shows) a flagrant violation of the court's order, Redrado said in a statement, adding that he had presented a legal complaint against Cabinet Chief Anibal Fernandez for impeding him from carrying out his duties.

President Cristina Fernandez fired Redrado earlier this month because he opposed her bid to use $6.6 billion in foreign currency reserves to service debt obligations this year, but a court ordered his reinstatement a day later.

Fernandez's push to tap the reserves to help meet some $13 billion in debt repayments this year has raised political tension in Latin America's No. 3 economy, rattling financial markets and raising concerns a planned $20 billion bond swap could be delayed.

Another court ruled on Friday that Congress should decide whether Fernandez was right to fire Redrado, but government ministers interpreted the ruling as also saying he had to quit.

The cabinet chief, Anibal Fernandez, said Redrado would not be allowed to continue working at the bank and the bank's board of directors named Vice President Miguel Pesce as Redrado's replacement.

Fernandez had already named Pesce as Redrado's replacement before the federal court ordered his reinstatement.

Constitutional experts and lawmakers from both the ruling party and opposition also said the latest ruling meant Redrado should step aside, but in a letter to a leading newspaper on Sunday, Redrado pledged to stay on in his job.

I maintain my decision to continue carrying out my duties as an official unless Congress says otherwise in order to comply with the law and my convictions, he wrote in the letter published in daily La Nacion.

A special congressional commission is due to meet on Tuesday to discuss Redrado's fate, but Fernandez has stressed that any recommendations it makes are nonbinding.

Friday's court rulings dealt another setback to the cash-strapped government's plan to tap part of the central bank's $48 billion in foreign reserves, upholding an earlier court freeze on the transfer of funds to the Treasury.

(Writing by Helen Popper; Editing by Tomasz Janowski)