(Adds Argentina, Brazil comments on Venezuela sanctions; adds details about trade agreements in paragraphs 12, 13)
MENDOZA, Argentina, July 21 (Reuters) - The members of South America's Mercosur trade bloc called for an end to violence in Venezuela in a joint statement on Friday, while Brazil and Argentina expressed wariness about following the United States in preparing possible economic sanctions.
Mercosur members Argentina, Brazil, Paraguay and Uruguay again called on Venezuela to release political prisoners and offered to facilitate talks between President Nicolas Maduro's socialist government and the opposition in the statement, issued as the nations met in Mendoza, Argentina to discuss trade and regional integration.
Associate Mercosur members Chile, Colombia and Guyana, as well as Mexico, also signed the statement, which called on both the government and the opposition to "not take any initiative that could divide Venezuelan society even more, or aggravate institutional conflicts."
The statement comes days after U.S. officials said they were preparing sanctions against Venezuelan government figures.
Brazilian Foreign Minister Aloysio Nunes and Argentine Foreign Minister Jorge Faurie told reporters Mercosur countries were hesitant to follow suit.
"None of us are willing to apply any sanctions that will affect, above all, the Venezuelan people," Faurie said.
Nunes said any Mercosur decision would be "autonomous" of U.S. action, and said interruptions of food shipments from Brazil to Venezuela could "aggravate the humanitarian crisis even more."
Venezuela was suspended from Mercosur last December amid concerns about human rights. Since then, four months of anti-government unrest has taken around 100 lives. On Friday, millions joined a 24-hour shutdown as part of a civil disobedience campaign against Maduro.
In April, Argentine President Mauricio Macri warned that Venezuela could be expelled from Mercosur if it did not change its behavior.
The joint statement did not refer to Maduro's plan to hold a July 30 vote to elect a constituent assembly with powers to rewrite the OPEC nation's constitution. Mexico on Thursday had called on Maduro to shelve the vote.
Bolivia, whose President Evo Morales is one of Maduro's few remaining allies in the region, is in the process of becoming a Mercosur member.
At the meeting, Mercosur members agreed to establish common legal conditions within the bloc to encourage investment and took steps to boost trade ties with the Pacific Alliance countries of Chile, Colombia, Mexico and Peru.
Mercosur is also eyeing a trade deal with the European Union, which Faurie said could be reached in December. (Reporting by Jorge Otaola; Writing by Luc Cohen; Editing by James Dalgleish)