US President Barack Obama and one of the most voluble critics of the United States, Venezuelan President Hugo Chavez, have cordially shaken hands as they met for the first time at a Summit of the Americas in Trinidad.

A Venezeulan official said on Friday: "It was only a matter of seconds. They saw each other, they greeted each other, as the official inauguration got underway. It was very brief. President Chavez greeted Obama in Spanish, and he responded in English."

The Venezuelan presidency supplied photos showing Chavez and Obama, both smiling and looking at ease, together.

Chavez was said to have told Obama at that moment: "I shook hands with (George W.) Bush with this hand eight years ago. I want to be your friend."

Obama responded by thanking Chavez, the official said.

Although Chavez maintains his tirades against the "imperialist" United States, he has expressed respect for Obama, in contrast with Bush, whom he called a "poor idiot."

The United States government, however, sees Venezuela as maintaining obscure relations with leftwing FARC guerrillas in neighboring Colombia and not doing enough to fight drug trafficking.

Chavez last September expelled the US ambassador to Caracas, prompting Washington to retaliate by ordering the Venezuelan ambassador out.