(CNN) The Trump administration's new special envoy on the Venezuelan political crisis is well known in Latin American circles -- from his guilty plea for withholding information about the Iran-Contra affair to his attempt to discredit accounts of the massacre of nearly 1,000 people by a US-trained military battalion in El Salvador.

"This crisis in Venezuela is deep and difficult and dangerous, and I can't wait to get to work on it," Abrams said after his appointment on Friday, noting that he left the State Department 30 years ago this week.

Pompeo warmly welcomed him back, saying Abrams' "passion for the rights and liberties of all peoples makes him a perfect fit and valuable and timely addition" to the State Department team.

Not all Latin American observers agree.

"Elliott Abrams, like his neo-conservative colleague John Bolton, believes in using US power to overthrow regimes Washington doesn't like, not negotiate with them," said William LeoGrande, an American University professor who specializes in Latin American politics and US foreign policy, referring to Trump's hawkish national security adviser.

"He is the wrong person for the job of Venezuelan envoy, because as long as the military remains loyal to Maduro, the only way out of the Venezuelan crisis is some sort negotiated settlement."

LeoGrande said Cuba could play a key role in reaching a negotiated settlement in Venezuela but both Abrams and Bolton have a long history of vilifying Cuba.

"Abrams, as assistant secretary of state for Latin America under George H.W. Bush, opposed allowing Cuba to join the US-sponsored talks between Angola and southern Africa in the late 1980s, delaying the end of the war in Angola by years," he said.

Abrams' controversial past in the region included his downplaying of human rights abuses by Central American governments close to the United States while serving at the State Department under President Ronald Reagan.

One instance involved the largest mass killing in recent Latin American history: the December 1981 massacre of nearly 1,000 men, women and children in the Salvadoran village of El Mozote by US-trained and -equipped military units.

Human Rights Watch report on the massacre said that Abrams at Senate hearings "artfully distorted several issues in order to discredit the public accounts of the massacre," insisted the numbers of reported victims were "implausible" and "lavished praise" on the military battalion behind the mass killings.

In 1991, facing a multi-count felony indictment, Abrams agreed to plead guilty to two misdemeanor counts for withholding information to Congress about the Iran-Contra affair. He was sentenced to two years probation and 100 hours of community service, and later pardoned by President George H.W. Bush.

The worst scandal of the Reagan administration, Iran-Contra involved the funding of anti-communist rebels in Nicaragua.

The secret operation was directed by the National Security Council's Oliver North and used the proceeds from weapon sales to Iran to fund the anti-communist Contras i n Nicaragua -- despite a congressional ban on such funding.

Friday, Pompeo called the resolution of the Venezuelan crisis "a global challenge."

"Elliott will have responsibility for all things related to our efforts to restore democracy in Venezuela," he said. "There are multiple dimensions to how we hope to assist the Venezuelans in achieving democracy there, and he will be responsible for leading that effort."