US President Barack Obama spoke with Venezuelan President Nicolas Maduro for the first time Saturday, telling him Washington was not seeking to threaten Caracas amid sky-high tensions.

US President Barack Obama spoke with Venezuelan President Nicolas Maduro for the first time Saturday, telling him Washington was not seeking to threaten Caracas amid sky-high tensions.

US officials said the two leaders met for a few minutes on the margins of the Summit of the Americas in Panama City, where Maduro used the stage to air his grievances about US sanctions against Venezuelan officials.

The brief encounter happened the same day that Obama held historic talks with Cuban President Raul Castro as part of their efforts to end decades of Cold War-era hostility.

Maduro told the summit that he respected but did not trust Obama, and that it was the US president who had threatened Venezuela. Obama had left the summit room before he spoke.

The White House had sought to ease tensions before the summit, saying it did not really believe that Venezuela posed a US national security threat, as stated in the sanctions document.

In his brief moment with Maduro, Obama voiced his support for a peaceful dialogue between Venezuela's government and the opposition, said Katherine Vargas, a White House spokeswoman.

The US leader also "reiterated that our interest is not in threatening Venezuela, but in supporting democracy, stability and prosperity in Venezuela and the region," Vargas said.

Maduro came to the 35-nation summit to demand that Obama lift sanctions executive order, saying he had garnered more than 13 million signature against it.

"I respect you, but I don't trust you, President Obama," Maduro told the summit, though Obama had already left to hold bilateral talks with Colombia's president.

Fellow leftist leaders from Argentina, Bolivia and Ecuador rallied behind Maduro.

"I am willing to talk with President Obama about this issue with respect and sincerity whenever he wants," Maduro said.

Maduro said he has publicly and privately sought to speak with Obama ever since the Venezuelan leader was elected two years ago, but his US counterpart "never answered the messages that I sent him."