By Marianna Parraga CARACAS, March 13 (Reuters) - Venezuela started production with Italy's ENI at a joint venture in its vast Orinoco belt on Wednesday, and officials expect output to begin soon at projects with Chevron and the China National Petroleum Corporation (CNPC). In addition, Oil Minister Rafael Ramirez said Venezuela's state oil company PDVSA will sign a long-awaited $2 billion credit agreement with Chevron at the end of this month. Ramirez has said that Venezuela will maintain its oil industry tax and legal framework under the leadership of acting President Nicolas Maduro, seeking to reassure foreign investors after last week's death of Hugo Chavez. "Today begins early production at our Petrojunin joint venture (with ENI)," Ramirez told reporters. "We're symbolically starting with 700 barrels per day (bpd). It will reach 15,000 bpd by the end of the year, and 75,000 bpd en 2015." The project has a production capacity of 240,000 bpd and a refinery will be built to process its extra heavy crude. PDVSA is focusing on the Orinoco extra heavy crude belt, where it also has projects with foreign companies including Spain's Repsol and Russia's Rosneft. Ramirez said production was expected to start in the coming weeks at a joint venture with China's CNPC and in May at the Carabobo 3 project, which includes Chevron. He said each one is forecast to be producing 15,000 bpd by the end of this year. Production began last September at Petromiranda, an Orinoco joint venture where PDVSA is partnered with a consortium of Russian companies, including Rosneft and Lukoil. Ramirez said Lukoil would be left out of PDVSA's plans until comments by its vice president and head of foreign projects, Andrei Kuzyayev, had been "clarified". He did not elaborate. Last week, Kuzyayev told Reuters that Venezuela could boost its oil output considerably in five to seven years if it offered investors greater certainty over contracts. PDVSA aims to boost its oil output by 500,000 bpd this year, which the government says would bring total production to 3.5 million bpd. Many industry experts question the official output figures from Caracas and say they are too high.