Sen. Tom Cotton (R., Ark.) said Thursday that the United States should not improve relations with Russia unless Russian President Vladimir Putin adopts "a new set of boundaries."
Cotton made the remarks at a national security summit hosted by Defense One after Republican President-elect Donald Trump expressed a desire to have a "strong and enduring relationship" with Moscow during a phone call with Putin.
"To improve our relations with Russia, what needs to happen foremost is Vladimir Putin needs to have a new set of boundaries," Cotton told an audience in Washington, D.C., on Thursday when asked whether he would be in favor of improving relations with Russia or lifting sanctions on Moscow imposed in response to its annexation of Ukraine's Crimean Peninsula in 2014.
Cotton said Russia would need to recognize the United States' commitment to its NATO allies in Europe, who have felt threatened by Russian aggression in the region. Cotton also said that Putin would need to "have a sense of reality" about the motivations of the alliance and realize that NATO is "not a threat to Russia."
"It would be good, of course, if we had a better relationship with our adversaries," Cotton said. "[The Russians] have to recognize that we are going to stand by our alliance structures."
Reports emerged earlier this week that Cotton was being considered to serve as defense secretary in Trump's administration. Sen. Jeff Sessions (R., Ala.), a close Trump ally, is considered the leading contender for the post.
Trump and Putin spoke about the U.S.-Russia relationship and a range of "threats and challenges" facing both nations, according to a statement released by Trump's transition team on Monday. The Kremlin said separately that the two discussed "normalizing" relations and cooperating on matters such as the war in Syria.
The revelation led Sen. John McCain (R., Ariz.), who chairs the Senate Armed Services Committee, to warn that a "reset" with Russia would be unacceptable and the price of it would be "complicity in Putin and Assad's butchery of the Syrian people."
Trump has said repeatedly that he wants America's allies pay more for defense. Currently, only five of 28 NATO members meet its guidelines for military spending.
Trump suggested in a New York Times interview in July that he would only come to the defense of a NATO partner invaded by Moscow if the country were meeting its defense spending obligations in the alliance.
When asked about the interview on Thursday, Cotton did not criticize Trump but noted that the United States is "ironclad in our support of our NATO allies" and that the treaty "protects our interests." The senator also distinguished between the commitments of the Article 5 principle, which says that an attack on one ally is an attack on all, and those related to defense spending.
"Article V is a treaty commitment, the 2 percent defense spending is a political commitment," Cotton said, noting that it would be a "good thing" if America's European allies paid more for defense.
Cotton said President Obama has enabled Russian aggression and allowed Putin to "achieve his national objectives."
Since the administration's "reset" with Russia in 2009 led by former secretary of state Hillary Clinton, relations between the United States and Russia have worsened. Moscow has flexed its military power by intervening in Ukraine and, later, worn-torn Syria, where Russian warplanes have been bombing U.S.-backed rebels fighting the Bashar al-Assad regime.
Russia has also adopted a more threatening posture toward NATO allies in Europe, and the United States and other member states have agreed on a plan to bolster forces on the alliance's eastern flank.
Cotton said Thursday that he believes Trump will be viewed by foreign leaders, including Putin, as stronger than Obama.
"Donald Trump has spoken about upholding our alliances as part of our core interests," Cotton said.
An Iraq and Afghanistan Army veteran, Cotton has been a vocal critic of Obama's foreign policy decisions, particularly the Iran nuclear deal and the administration's push to close the military prison at Guantanamo Bay Naval Base, Cuba.
He refused to address on Thursday whether Trump had contacted him about serving as defense secretary.
"President-elect Trump will make these decisions in his own due time," Cotton said, noting that a decision may not be made until after the Thanksgiving holiday. "I think we should let him take that time."