(CNN) - Newt Gingrich called on his supporters and staff Tuesday to "stay positive" and avoid attacking fellow Republican presidential candidates, the day after he engaged in a verbal back-and-forth with Mitt Romney.
In an email, the former House speaker said he would refrain from attacking other candidates so the GOP nominee emerges from the primary season "un-bloodied," and encouraged his backers and other Republican contenders to do the same.
"I am instructing all members of my campaign staff and respectfully urge anyone acting as a surrogate for our campaign to avoid initiating attacks on other Republican candidates," Gingrich wrote. "It is my hope that my Republican opponents will join me in this commitment."
On Monday, Gingrich and rival candidate Romney sniped at each other over their records in the private sector. In Tuesday's letter, Gingrich categorized the comments from both camps as "a frank exchange," saying he "reserved the right to respond when my record has been distorted."
But, echoing similar sentiments from Romney, Gingrich said he hopes the candidates will run a solutions-based campaign to ensure President Barack Obama is not elected to a second term.
"So let us hope that from this point forward we can devote our energies to real issues, such as discussing our plans for our nation's economic recovery and helping to create millions of new jobs for the American people," Gingrich wrote.
The letter comes amid heightened attacks against Gingrich from Romney, his closest competitor for the 2012 GOP nomination. The former Massachusetts governor launched a full-scale assault on Gingrich's record, including calling on the former speaker to return the millions of dollars he earned consulting for Freddie Mac.
Gingrich responded by calling on Romney to return the money he earned during his tenure at Bain Capital, saying Romney was responsible for "bankrupting companies and laying off employees."
Gingrich's letter Tuesday mirrors sentiments he made at a town hall in New Hampshire Monday, when he told voters he saw the race going in a direction that could damage a potential 2012 GOP nominee.
"In the last week or so, as I've gotten to be more of a frontrunner, the campaign has begun for the first time to really degenerate in terms of some of the ads, particularly in Iowa," Gingrich said in Windham, New Hampshire. "I appreciate Governor Romney taking that position, and I agree with him, I think what we're about is too important to weaken anybody who might defeat Barack Obama and to give Barack Obama any ammunition that he shouldn't have."
At the event, Gingrich vowed to disassociate himself with any independent political groups that run negative ads against other candidates, and advised the crowd not to donate to any Super PAC that produces negative advertising.
"The choice of the president of the United States, at a time of genuine troubles, is not a game," Gingrich said. "It isn't who can hire the meanest, nastiest, or most creative consultant. It is a fundamental choice about who we think can provide the solutions that bring us together as a nation."