CARACAS, Nov 30 (Reuters) - Venezuela on Monday shut down four private banks a day after socialist President Hugo Chavez warned he would not hesitate to nationalize any financial institutions failing to help national development.

Anxious staff and depositors gathered outside bank offices, whose doors stayed shut after Finance Minister Ali Rodriguez called an early-morning news conference to announce their closure due to internal irregularities.

"How can I pay for my shopping, my boy's school? How will I survive? Who will answer for my money?" said employee and depositor Fabiola Martin, among 200 people thronging the Caracas headquarters of one of the banks, Banco Canarias.

The four banks account for just 6 percent of the South American nation's deposits, and were taken over by the government on Nov. 20 for violations of solvency regulations and unexplained capital increases.

Their owner, wealthy businessman Ricardo Fernandez who has close ties to the government including supplying state shops with food, is under arrest. A court has barred 16 of the banks' executives from leaving the country.

"The negative performance of the banks makes their closed-door intervention necessary," Finance Minister Ali Rodriguez said, reading a statement.

Two of the institutions -- Banco Provivienda and Banco Canarias -- would be "liquidated", though more than 90 percent of their 725,000 depositors would be protected by the government's bank insurance agency Fogade, he said.

The financial problems at the other two -- Banco Confederado and bolivar Banco -- were less severe, and those institutions could be rescued, Rodriguez added. Analysts said that could likely spell a formal government takeover.

During his decade in power, Chavez has taken over large swathes of the OPEC member nation's economy -- including oil projects, telecommunications and power firms, and farmland -- as part of his policies of "21st century socialism".

But Monday's closures appeared to be directly related to the problems of those four banks, and its owner's deteriorating relationship with the Chavez government, rather than the start of a major new wave of takeovers, analysts said.

MORE 'CLEANING' COMING?

The only major private bank to have fallen into state hands under Chavez was Spain's Banco Santander (SAN.MC) unit Banco de Venezuela, sold in July for $1.05 billion. Ten large banks, of a total of near 50, account for 70 percent of deposits. Continued...