John Bolton announced Thursday that he will not run for president, ending speculation that the former U.N. ambassador might add his name to the growing and crowded Republican primary field. 

“Looking forward, I have decided not to seek the Republican nomination for president,” he said in a statement Thursday. “I believe I can make the strongest contribution to our future by continuing as a clear and consistent advocate for a strong Reaganite foreign policy that values peace through strength.”  

Bolton, a lawyer and fellow at the American Enterprise Institute who is also a frequent guest on the Fox News Channel, served in both the George W. Bush and George H.W. Bush White Houses. His last position, as U.S. ambassador to the U.N. from 2005 to 2006, put him at the top level of policymaking during the most volatile years of the Iraq and Afghanistan wars. Just after 9/11, he served as President Bush’s undersecretary of state for arms control and international security affairs. Bolton was assistant secretary of state for international organization affairs under the senior Bush.  

Bolton’s hawkish positions, particularly on Iran and Syria and the pull-out of military forces from Iraq, have put him squarely against the current administration. He made it known that his decision not to run for president does not mean he would not be involved in the 2016 race some other way. He was an adviser to presidential candidate Mitt Romney in 2012, and has reportedly been advising, informally, 2016 candidate Sen. Ted Cruz.  

“I cannot sit idle while the President surrenders our national interests, and liberals rally around Hillary Clinton," he said. "I’m going to keep an eye on the 2016 Republican field, through my PACs I'll continue to support candidates for public office, and through my foundation make certain foreign policy is a priority issue in elections over the next two years.”