MSNBC apologizes for Cheerios tweet that offended Republicans WASHINGTON (Reuters) - Republican National Committee Chairman Reince Priebus said on Thursday he accepted an apology from the president of MSNBC over a tweet from the network that said "the rightwing" might disapprove of a Cheerios television ad featuring a biracial family. MSNBC President Phil Griffin issued a statement saying the staffer responsible for the Wednesday night tweet had been fired. "The tweet last night was outrageous and unacceptable," Griffin said. We immediately acknowledged that it was offensive and wrong, apologized, and deleted it ... I personally apologize to Mr. Priebus and to everyone offended. Priebus had banned RNC staffers from appearing on MSNBC, urged other Republicans to follow suit and demanded an apology because of the Twitter posting. The cable news network's tweet said: "Maybe the rightwing will hate it, but everyone else will go awww: the adorable new #Cheerios ad w/ biracial family." The tweet was sent to promote an MSNBC story on the breakfast cereal commercial, which will be broadcast during Sunday's Super Bowl. The ad stars Grace Colbert, 6, as the daughter of a fictional biracial couple. Last year, she was in a similar Cheerios commercial, which triggered racist comments when it was posted on YouTube, Google Inc's video-sharing site. An RNC statement said Priebus and Griffin spoke by phone on Thursday and that the party would continue to monitor the network, which is seen as having a liberal bent. "We don't expect their liberal bias to change but we will call them out when political commentary devolves into personal and belittling attacks," the statement said. In a letter to Griffin, Priebus had said the Cheerios tweet showed that MSNBC "is poisoned by this pattern of behavior." "Sadly, such petty and demeaning attacks have become a pattern at your network," Priebus said. With increasing frequency many of your hosts have personally denigrated Americans - especially conservative and Republican Americans - without even attempting further meaningful political dialogue. Earlier this month, MSNBC host Melissa Harris-Perry apologized on the air for a segment that joked about the adopted black grandson of Mitt Romney, the Republicans' unsuccessful 2012 presidential candidate. The segment featured a photo of Romney and his wife with their grandchildren and members of a panel were asked to suggest captions. Actress Pia Glenn sang that "one of these things is not like the others," while comedian Dean Obeidallah joked that the photo "really sums up the diversity of the Republican Party." Romney later accepted Harris-Perry's apology. In December, correspondent Martin Bashir apologized and resigned from MSNBC because of graphic on-air comments he made about former Republican vice presidential candidate Sarah Palin. In November, actor Alec Baldwin was suspended from his MSNBC show after he used a homophobic term in a confrontation with a photographer on a New York street. Baldwin's show was later canceled. Reporting and writing by Bill Trott; Editing by Peter Cooney, G Crosse and Mohammad Zargham