Ernesto Samper, secretary-general of the Union of South American Nations (UNASUR), reentered the United States Friday nearly 20 years after having his visa revoked over allegations of ties to a drug cartel. Reuters/Carlos Garcia Rawlins

A former Colombian president returned to the U.S. nearly 20 years after the Clinton administration revoked his visa over allegations of ties to a drug cartel. Ernesto Samper, now the head of South American regional organization Unasur, tweeted a photo of himself at the United Nations headquarters in New York City Friday.

The visa issue apparently didn’t give Samper any problems entering the country: According to Colombian news magazine Semana, he passed through immigration officials with a diplomatic passport available to him as the head of Unasur. United Nations Secretary-General Ban Ki-moon reportedly invited Samper to the U.N. headquarters to discuss future cooperation with Unasur. Semana also published a photo of Samper standing on a New York City street with the Chrysler building towering behind him.

Former U.S. President Bill Clinton stripped Samper of his U.S. visa in 1996 amid accusations that Samper had knowingly accepted campaign donations from the Cali drug cartel, one of the biggest distributors of illicit drugs in the 1980s and 1990s, in exchange for lenience on the organization. Samper has continually denied that he knew about any such contributions to his campaign and was cleared of any wrongdoing, although some members of his campaign staff were convicted over the incident.

The Cali cartel is now considered defunct. Last year the U.S. lifted sanctions against 308 individuals and companies that had been blacklisted over ties to the organization, but it never reinstated Samper’s visa.

Samper became Unasur’s chief in September after being appointed by a council of foreign ministers. He is in the middle of a two-year term, which he will be able to renew once.

Unasur has been trying to broker dialogue between Venezuela and Guyana over a maritime border dispute that has flared up in recent weeks, a topic that likely came up during Samper’s meeting with Ban Friday. Venezuela’s foreign minister, Delcy Rodriguez, said Friday it would ask the United Nations to assign a formal mediator to help resolve the conflict, according to the Associated Press. At Friday’s U.N. meeting, Samper said he welcomed “any approach” toward resolving the Venezuela-Guyana dispute.