He said Maduro's frequent accusations that the U.S. is participating in a conspiracy against his government have made it difficult for the U.S. to influence the situation.
"We have become an excuse, we are a card they play," Kerry said. "I regret that because we pretty much opened up and reached out in an effort to say, 'It doesn't have to be this way.'"
The UNASUR group of South American nations said Wednesday that it will send a commission of foreign ministers to Venezuela in April to encourage dialogue on resolving the political conflict. The Venezuelan political opposition and student leaders have refused to speak with the government until it releases jailed protesters.
Associated Press writers Luis Alonso Lugo in Washington, Andrew Rosati in Caracas, Vivian Sequera in Bogota and Luis Andres Henao in Santiago contributed to this report.
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