DUBAI (Reuters) - Yemen's Houthi movement and supporters of former president Ali Abdullah Saleh criticised the country's exiled government on Tuesday for appointing a new head of the central bank and relocating it to Aden.

Exiled president Abd-Rabbu Mansur Hadi appointed Monasser Saleh al-Quaiti as governor on Sunday and ordered the bank to move to the government-held southern city from Sanaa, escalating a struggle over the finances of the impoverished country.

The bank's newly appointed governor has said the armed Houthi movement that controls Sanaa has been pillaging it to finance its war against the exiled government.

The governing council of Houthis and Saleh supporters said in a statement that the "unprecedented move reflects the desperation and lack of direction that the Saudi regime and its supporters in Riyadh had reached."

It said the central bank in Sanaa, currently run by veteran governor Mohamed Bin Humam, should be the only legitimate monetary authority.

"This act from a legal perspective is null and void," it said. "We call on the international community especially the international monetary and financial institutions to stand by their decision to reject that move."

The leader of the Iran-allied Houthi faction Abdel-Malek Al-Houthi on Al Manar television, the Lebanese Hezbollah's official station, that the move was mainly directed by the United States and appealed to Yemenis to support the bank in Sanaa.

"Whoever can contribute should contribute, whether it is fifty riyals or a hundred or a thousand, and then you will see how the bank will stand strong in the face of the conspiracies it faces," he said.

The newly appointed governor Quaiti said on Monday that salaries paid by the central bank to pro-Houthi soldiers and officials have reduced Yemeni foreign exchange reserves from $5.2 billion in September 2014 to less than $700 million by the end of August. [nL8N1BV2TI]

Still, diplomats largely agree that the bank has maintained its impartiality throughout the 18-month civil war, remaining the last pillar of Yemen's financial system and guaranteeing imports of key food staples - a job that becomes harder as foreign exchange reserves dwindle. [nL8N1B54SM]

(Reporting by Noah Browning and Ali Abdelaty; Writing By Maha El Dahan; Editing by Tom Heneghan)