BOGOTA, Colombia (CBSDFW.COM/AP) — Texas Republican congressman Pete Sessions quietly visited Venezuela this week and met with President Nicolas Maduro at the invitation of the socialist government in a peacebuilding mission that has raised some eyebrows in Washington.

It’s not clear what prompted the previously undisclosed visit by the Dallas congressman to the politically turbulent South American nation.

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Rep. Pete Sessions, R-Texas, speaks with reporters as he leaves the House Republican Conference meeting in the Capitol on Tuesday, Jan. 9, 2018. (Photo By Bill Clark/CQ Roll Call)

Caroline Booth, a spokeswoman for the congressman, said it was related to work Sessions has done over the past year as an intermediary to resolve issues in Venezuela, but she declined to elaborate. She added that as chairman of the powerful House Rules Committee he routinely works to ensure countries adhere to international standards and the rule of law.

The two-day trip came as Maduro’s government is making a full-court press to prevent the Trump administration from imposing crippling oil sanctions on the OPEC nation for what the United States considers Maduro’s flaunting of human rights and democratic norms.

A U.S. official said the private trip was not taxpayer funded and that Sessions had received a letter of invitation from the Venezuelan government and met with Maduro. He said State Department officials played no role in organizing the trip, which ended Tuesday and added that they were not invited to sit in on Sessions’ meetings as they were by Sen. Dick Durbin, the No. 2 Democrat, who arrived in Caracas on Wednesday for his own meetings with Maduro and government officials.

The U.S. official agreed to give details on Sessions’ trip only on condition of anonymity because they weren’t authorized to discuss it publicly.

Durbin is in Venezuela to push for the release of a Utah man, Joshua Holt, who has been jailed in Caracas for nearly two years on what the U.S. considers trumped-up weapons charges. The senator also planned to deliver a stern message to Maduro that he must guarantee upcoming the presidential election will be free and transparent.

Sessions doesn’t have other obvious links to Venezuela, besides writing a letter in 2004 to the country’s banking regulators in support of financier Allen Stanford, a former Sessions donor who in 2012 was convicted in Texas and sentenced to 110 years in prison for running a $7 billion-plus Ponzi scheme.

He also voted in favor of a bipartisan House bill last year directing the Trump administration to secure international support for a humanitarian package for Venezuela and to work with regional governments to ensure protection for human rights and transparent elections in the country.

Sessions has been in Congress since 1997, representing a wealthy Dallas district that is home to Exxon and other oil companies that were once major players in Venezuela’s oil industry but have since ended or dramatically reduced their investments in the country as oil production has collapsed and the bankrupt Maduro government falls behind on payments.

Texas is also home to Citgo, a wholly owned subsidiary of Venezuela’s state oil company. Last year, several of the company’s executives, including five who hold U.S. passports, were arrested by Venezuelan authorities in a corruption investigation that critics say is politically motivated.

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Sessions, whose father is former FBI Director William Sessions, hasn’t faced a serious challenge for re-election in more than a decade and didn’t even have a Democratic opponent in 2016. But his district narrowly supported Hillary Clinton over Donald Trump, prompting speculation that it could flip this cycle.

Rep. Sessions is up for re-election in November.

After 21 years in Congress, he seems unfazed by Democrats’ who are energized this year. “I’ve not lost an hour’s sleep yet. I’ve not been worried about it. But this will be a vigorous debate.”

Congressman Sessions says his message to his Republican supporters is about the booming U.S. economy under President Donald Trump. “America’s going to go from 24th in the world to doing business to 1st.  We’re going to make America strong.  We’re going to bring back economically the American people, the American free-enterprise system.  And we’re going to take people off welfare and allow them to move to work at their rate.”

Sessions says one of his top priorities is safety — for the military, law enforcement, and students.

Polls show a majority of Americans support keeping guns away from the mentally ill.

Sessions says he agrees.

When asked if he would support a bill that would do that he said he would if it includes due process rights for individuals.

He says it was a lack of due process that led him and the Republican-led Congress to wipe out an Obama administration rule aimed at keeping guns away from the mentally ill.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)