(CNN) – Richard Grenell, who joined Mitt Romney's team as a foreign policy adviser less than two weeks ago, has left the campaign, a spokesman for the likely Republican presidential nominee confirmed Tuesday.
"We are disappointed that Ric decided to resign from the campaign for his own personal reasons," campaign manager Matt Rhoades said in a statement. "We wanted him to stay because he had superior qualifications for the position he was hired to fill."
Since joining the campaign in mid-April, Grenell's short tenure has been marked by controversy involving his Twitter account, as well as heavy criticism of Grenell's sexual orientation from some on the conservative right. The longtime Republican strategist is openly gay.
Most pressing, Grenell faced recent scrutiny over reports that he had deleted hundreds of posts on Twitter shortly after being appointed by the Romney campaign.
The tweets, written prior to his hiring, criticized the physical appearances of certain high-profile Democratic women, including Secretary of State Hillary Clinton and MSNBC host Rachel Maddow.
Archived online, the Twitter posts also included several jabs aimed at Newt Gingrich and his wife, Callista, during the Republican presidential primary.
Grenell previously served in the George W. Bush administration as a communications director at the United Nations and an adviser to four U.S. ambassadors to the U.N.
Also since joining the Romney campaign, Grenell has taken heat from the anti-gay group American Family Association.
Writing in a blog last week, Bryan Fischer, a director for the conservative group, argued: "The message Gov. Romney appears to be sending to the pro-family community through his Grenell appointment is 'drop dead'."
Later, during an interview on CNN, Fischer referred to Grenell's hire as a "big gain for the homosexual lobby."
In a statement obtained by the Washington Post, Grenell pointed to the public discussion over his sexual orientation as a reason for leaving the campaign.
"While I welcomed the challenge to confront President Obama's foreign policy failures and weak leadership on the world stage, my ability to speak clearly and forcefully on the issues has been greatly diminished by the hyper-partisan discussion of personal issues that sometimes comes from a presidential campaign," Grenell said in the statement.
He added: "I want to thank Governor Romney for his belief in me and my abilities and his clear message to me that being openly gay was a non-issue for him and his team."
- CNN National Political Correspondent Jim Acosta contributed to this report.