Defense Secretary Jim Mattis addresses a news conference after a NATO Defence Ministers’ meeting at the NATO headquarters in Brussels on Feb. 16. (Thierry Charlier/Agence France-Presse)

BRUSSELS — Defense Secretary Jim Mattis said Thursday that Russia will need to “prove itself first” before the United States and other members of the North Atlantic Treaty Organization are willing to let their armed forces collaborate, potentially complicating efforts by President Trump and Russian President Vladimir Putin to cooperate in the fight against the Islamic State in Syria.

Mattis, speaking at NATO’s headquarters in Brussels, told reporters that the conditions are not right presently for U.S. and Russia forces to work together. The Pentagon and the Kremlin all but broke contact entirely in 2014, after Russia’s annexation of Ukraine’s Crimean peninsula prompted international outcry.

“We are not in a position right now to collaborate on a military level, but our political leaders will engage and try to find common ground or a way forward so that Russia, living up to its commitment, can return to a partnership of sorts here with NATO,” Mattis said.

Mattis’s comments came just ahead of him leading a meeting at NATO on the effort to counter the Islamic State, and after Putin suggesting Thursday that improving ties between Russian and U.S. intelligence services makes sense.

“Cooperation in the anti-terrorist sphere should be taken to a new level with foreign partners,” Putin said at an annual meeting of senior leaders of the FSB, Russia’s foreign intelligence agency. “It is our common interest to restore dialogue with the U.S. intelligence services and those of other NATO countries.”

Marine Gen. Joseph F. Dunford, the chairman of the Joint Chiefs of Staff, also met Thursday with Gen. Valeriy Gerasimov, Russia’s top military officer, in Azerbaijan’s capital, Baku. The encounter marked the first time that senior Pentagon officials and their Russian counterparts have met in person since 2014. Russian and U.S. defense officials periodically discuss air operations over Syria to make sure that they avoid potential conflicts, but those have been among the only interactions since.

Trump has raised the prospect of the United States and Russia collaborating to fight Islamic State militants in Syria since he was on the campaign trail, and he and Putin discussed possibilities last month in a phone call, according to the White House. But the issue is complicated by war crimes that both Russia and the Syrian government, which collaborate with the Russians, are accused of committing, and Russia’s alleged interference in the 2016 U.S. presidential election.

Mattis, who has called Russia the No. 1 threat to U.S. security, said Thursday that there is “very little doubt” that the Russians have “either interfered, or attempted to interfere in a number of elections in the democracies,” without explicitly naming the United States as one of them.

On Wednesday, Mattis issued a stern warning to NATO allies, saying that if they did not boost their defense spending to goals the alliance set in 2014, the United States may alter its relationship with them. He cited threats posed by Russia and its behavior over the past few years as primary reasons for the need to do so.

“I owe it to you all to give you clarity on the political reality in the United States and to state the fair demand from my country’s people in concrete terms,” Mattis said, according to a prepared versions of remarks he made behind closed doors. “America will meet its responsibilities, but if your nations do not want to see America moderate its commitment to the alliance, each of your capitals needs to show its support for our common defense.”

Mattis added that American taxpayers can no longer carry a disproportionate share of the defense of Western values, and that “America cannot care more for your children’s security than you do.”

Russia’s defense minister, Gen. Sergei Shoigu, responded afterward that he expected the Pentagon’s position would be clarified when Dunford met Gerasimov. Attempts to build a diplomatic dialogue with Russia from a position of strength are “fruitless,” Shoigu said, according to the Russian news agency TASS.

Mattis said Thursday that he does not need to respond to Shoigu’s statement, and that NATO has long stood for a strong military defense. But he also played down his ultimatum, saying that his remarks were well received by NATO’s defense ministers and that the United States was not backing away from its NATO treaty obligations, which stipulate that an attack on one NATO nation is an attack on all of them.

Mattis, asked to elaborate on what he meant by the United States potentially moderating its commitment to NATO nations, said he would prefer not to do so because he does not anticipate it happening.

“By putting it out there among friends we say, ‘This is a burden we all have to carry equally,’ and by being persuasive there, we will write our own headlines as a unified alliance that will stand up for each other,” Mattis said. “Sometimes, you say the thing you do not want to have happen so that you head them off.”

Mattis’s firm line toward the Kremlin was welcomed by NATO members who share a front-line border with Russia.

“You need to be very concrete” with Russia, Estonian Defense Minister Margus Tsahkna said in an interview. “If they’re doing something, then you have to have a very precise and concrete answer.”

Mattis, at the outset of the meeting on the Islamic State effort, said the mission is “not something that will be over with quickly, but we certainly need to accelerate this fight.

“One of the reasons we’re here today,” the defense secretary said, “is to lay this out to you.”

Mattis also met bilaterally with leaders from several countries, including French Defense Minister Jean-Yves Le Drian, a major partner in the action against the Islamic State in Syria and Iraq.

French leaders have been pushing for swift action against the Islamic State stronghold of Raqqa, which has been a planning hub for many of the terrorist attacks against Europe in recent years.

An official briefed on the meeting between Mattis and Le Drian said that the French defense chief supported any U.S. plan “that brings ideas for a more intense campaign in Raqqa.” Le Drian opposed a full-scale shift in Raqqa planning, the official said, saying that “the current plan that has been worked out over the last year is pretty coherent.”

Intensifying plans currently in place could envision a larger role for U.S. and French special forces trainers operating in Syria.

The Obama administration spent months developing a battle plan to seize Raqqa but ran out of time to execute it, leaving it for Trump to pull the trigger. But after the inauguration, Trump officials decided that the plans were wholly insufficient. The Pentagon is nearing the end of a 30-day review of battle plans for the Islamic State.


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