An irate President Anastasio Somoza accused Venezuelan President Carlos Andres Perez yesterday of trying to "provoke a bloodbath in my country."

Somoza, whose country's economy has been badly damaged by a strong and sometimes violent opposition movement, said his government "reserves the right to defend itself with all the constitutional resources" as its command.

Venezuelan President perez, the target of Somoza's wrath, has strongly criticized alleged violations of human rights here and has urged the United Nations and the Organization of American States to investigate.

"I call on all member states of the OAS not to allow themselves to be used for these maneuvers," Somoza said. Asked if Nicaragua would break relations with Venezuela, Somoza said, "It's a possibility."

Somoza met with foreign reporters as a nationwide general strike called by oppositive politicians and supported by business and labor went into its 12th day. The strike's goal is to force Somoza, whose family has ruled Nicaragua for more than 44 years, out of office.

A diplomatic source estimated that 95 percent of the large stores in Managua and 79 percent of the factories were closed yesterday. The source said the industries that remained open were owned by the Sumoza family or the president's supporters. The strike is generally thought to be stronger in the provinces than in the capital.

At the news conference, Somoza said 50 percent of the stores in the country are open.

While businessman worked to keep the strike going, supporters of the leftist Sandinista guerrillas continued to put up barricades in the slums and throw small bombs during the night. The National Guard, the country's combined armed forces and police, patrolled the slums and residents of nearby neighborhoods reported hearing gunfire during the night.

The president's office announced that some buses - which have continued to run during the strike - have been burned. Most private bus lines are owned by National Guard officers loyal to Somoza. The presidential statement said nighttime bus service would be stopped, some routes would be changed and a fare increase would be studied.

The government announced Monday night that 70 persons arrested recently had been released. Somoza told reporters at the news conference that 135 people were in custody and would be charged.

Somoza said those arrested were "people caught throwing bombs in the streets, making barricades and threatening to close shops." Asked about businessmen who have been jailed, the president said they had signed a document proposing "a government of national unity" to rule Nicaragua until a new president can be elected.

"That is not provided for in our constitution so they have violated the constitution and that is an offense in Nicaragua," Somoza said. In a development that appeared to strengthen the strike, a group of bank employes announced that they had organized a committee to support the strike and would stay away from their jobs. So far, the owners of the main banks have not joined the strike.

Outside the Banco de America (which is not linked to the U.S.-based Bank of America), the only skyscraper unscathed in the 1972 earthquake, about 100 strikers listened to speeches and chanted anti-Somoza slogans.

"We're the Sandinista bankers," one young man told a reporter.

At a smaller bank, a few supervisory employes allowed customers to do business although most of the bank's employes were on strike. The supervisors said they support the strike, but could not participate because of government pressure.

Asked about Somoza's statement in an interview Monday night that the "rank and file" of Nicaragua support him, the half dozen people in the bank laughed.

"The worst blind man is the one who does not wish to see," said a bank officer.