(CNN) -- CNN's senior Middle East editor, Octavia Nasr, has left the network after a controversial posting on Twitter about a Shia cleric who had longtime ties to and voiced strong support for Hezbollah.
Nasr, who joined CNN in 1990, posted a Tweet over the weekend that said, "Sad to hear of the passing of Sayyed Mohammad Hussein Fadlallah.. One of Hezbollah's giants I respect a lot."
The U.S. State Department classifies the Lebanon-based Hezbollah as a foreign terrorist organization.
In her position, Nasr provided on-air context for Middle East events and monitored the media from that region.
Nasr's posting "created a wide reaction," said Parisa Khosravi, senior vice president of international newsgathering for CNN Worldwide.
"As she has stated in her blog on CNN.com, she fully accepts that she should not have made such a simplistic comment without any context whatsoever," Khosravi said in an e-mail Wednesday to staff. "However, at this point, we believe that her credibility in her position as senior editor for Middle Eastern affairs has been compromised going forward."
Nasr addressed the issue in a CNN blog posting Tuesday.
"Reaction to my tweet was immediate, overwhelming and a provides a good lesson on why 140 characters should not be used to comment on controversial or sensitive issues, especially those dealing with the Middle East," Nasr wrote.
"It was an error of judgment for me to write such a simplistic comment and I'm sorry because it conveyed that I supported Fadlallah's life's work. That's not the case at all."
The Tweet was "something I deeply regret," Nasr wrote.
"As a colleague and friend we're going to miss seeing Octavia everyday. She has been an extremely dedicated and committed part of our team," Khosravi's e-mail said.
Prior to joining CNN, Nasr worked for the Lebanese Broadcasting Corporation, where she began her journalism career in 1985.