Venezuelan Foreign Minister Delcy Rodriguez during one of her interventions at an Organization of American States assembly in Cancun, Mexico. (Screengrab: YouTube)

(CNSNews.com) – Venezuela’s fiery foreign minister clashed with a senior U.S. diplomat at an Organization of American States meeting Tuesday, saying mockingly that the only way a regional mediation initiative responding to the crisis in her country could be imposed on Venezuela would be to “send in your Marines.”

Foreign Minister Delcy Rodriguez did not take kindly to a proposal by Mexico’s foreign minister that the OAS set up a regional “contact group” in response to the political and economic crisis in the socialist-ruled country.

U.S. Deputy Secretary of State John Sullivan urged the OAS meeting in Cancun to “take a modest step to put together a group that would help facilitate a resolution of the serious problems which we all acknowledge are present in Venezuela.”

If the 34-member regional grouping could not agree on that at the very least, he said, “we seriously impair our ability to go forward as an organization.”

Moments later Rodriguez hit back at Sullivan, calling the contact group proposal useless and unnecessary.

“The only way you could impose it would be to send in your Marines – who would meet with a crushing response from Venezuela if they dared make such a misstep,” she jeered.

Earlier, Rodriguez suggested U.S. wanted to intervene in her country in order to exploit its oil reserves.

Sullivan dismissed the arguments she put forward as “distractions, distortions, and irrelevancies.”

“The facts on the ground in Venezuela are apparent to all of us,” he said. “This is a moment of challenge for this organization to prove its relevancy.”

On Monday, the OAS failed to pass a resolution condemning President Nicolas Maduro’s controversial plan to convene a constituent assembly late next month to rewrite Venezuela’s constitution, thus bypassing the opposition-controlled National Assembly.

The motion received 20 votes, three short of the two-thirds majority required.

At least 70 people have been killed since April during protests against Maduro’s actions, including attempts to strip the National Assembly of its power to make laws. An accompanying economic crisis is reflected in sky-high inflation and severe shortages of food, medicines and other items.

The meeting in Cancun, which runs through Wednesday, has seen a walkout and several outbursts from Rodriguez, who derided Venezuela’s Latin American critics, calling them “lapdogs of imperialism” and – in the case of her Costa Rican counterpart Manuel González Sanz – a “political illiterate who knows nothing about Venezuela.”

González’ criticism appeared to irk the Venezuelan representative in particular. He had urged the OAS to condemn the Maduro regime for “violent acts, the economic and political crisis, the shortages of food and medicines, and the violation of rights and freedoms.”

In her response to González, Rodriguez also took another swipe at the United States.

“You should address the main country that causes inequality and hunger – not only in this region but in the whole world, of violence, death, and all the problems you have,” she told the Costa Rican. “But that is never going to happen because you are reading from a script …”

On Monday, U.S. Deputy Assistant Secretary Michael Fitzpatrick at a press briefing in Cancun warned that Maduro’s government would be accountable for the consequences if it goes ahead with the deeply-unpopular plan to rewrite the constitution.

“Should the Maduro regime decide to ignore the national and international outrage and appeals, and instead proceed to do away with the constitution in a patently illegal and dangerous manner in the context of an already polarized society,” he said, “the regime will bear a special responsibility for whatever befalls Venezuela thereafter.”