Caracas, September 9 (teleSUR-RHC)-- Venezuelan Foreign Minister Delcy Rodriguez Tuesday said U.S. Secretary of State John Kerry called her in an attempt to normalize relations between the two countries, which became increasingly tense in March after President Barack Obama ordered unilateral sanctions against Venezuela. The conversation with Kerry was “fluid and at times tense,” Rodriguez said on tweeter. Rodriguez said she would later give more details about the phone conversation with Kerry. In late August, Rodriguez said she called Kerry to ask him to stop interfering in Venezuela's internal affairs, saying they were in violation of international law. She told him that relations between both countries must be based on mutual respect. This was in response to Kerry's comments that international observers should be involved in Venezuela’s upcoming National Assembly elections and that all “political prisoners” in Venezuela should be freed, so that there would be no “negative impact” on U.S.-Venezuela relations. Rodriguez said Venezuela is a free and independent country and added: “The times in which the U.S. dictated norms to Venezuela are over, thanks to the anti-imperialist actions of the Venezuelan people.” Kerry’s claims about political prisoners refers to politicians arrested not for their political views but their orchestration of a wave of violence that led to the deaths of 43 people in 2014. Venezuela and the U.S. have not had ambassadors in each other’s countries since 2010, when Venezuela refused to admit the newly appointed U.S. ambassador because of negative comments he made about Venezuela’s military during his senate confirmation hearing. The U.S. subsequently expelled Venezuela’s ambassador, Bernardo Alvarez. Ever since, there have been negotiations on and off between the two countries about the exchange of ambassadors. The most recent effort was torpedoed by President Obama’s issuing of an executive order that declared Venezuela an “extraordinary and unusual threat” to U.S. national security and imposed sanctions on several Venezuelan government officials. The action prompted international condemnation, calling Obama's statement absurd. Since then, new negotiations have taken place at the initiative of President Maduro.