WASHINGTON — Secretary of State Antony Blinken suggested Thursday that the war in Ukraine is unlikely to end very quickly, and that it will to take time for sanctions to slow down Russian President Vladimir Putin as he threatens a vicious escalation.

“We also have to, I think, tragically, be prepared for this to go on for some time,” Blinken said.

A day after warning about the potential for a Russian chemical weapons attack, Blinken said sanctions are biting Russia — its economy is “in a free fall,” he said — but acknowledged that they are unlikely to have an immediate deterrent effect.

“The problem is it’s not flipping a light switch,” Blinken told The Inquirer and a handful of other news outlets over Zoom. “It does take time for them to reassess, calculate their interests and to see that what they’re doing is profoundly not in their own interest.”

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He also defended President Joe Biden’s decision not to enforce a no-fly zone over Ukraine, despite an emotional plea from Ukrainian President Volodymyr Zelensky.

“We obviously have an incentive in trying to end this war as quickly as possible, not to expand it, including to places beyond Ukraine,” Blinken said.

After Zelensky pleaded for a no-fly zone and other aid in a speech to Congress Wednesday, some Republicans said Biden was being too cautious. While most members of both parties oppose a no-fly zone, which could draw the U.S. into a direct military clash with Russia, they said Biden could do more, including by facilitating the transfer of fighter jets to Ukraine.

Blinken said Biden was providing the most effective military equipment possible while balancing U.S. help against his determination to avoid a direct military confrontation that could quickly draw in much of Europe.

“We’re determined to support Ukraine, and we are. We’re determined to exert extraordinary pressure on Russia, and we are,” Blinken said, “but the most important thing is, he’s got to do all that making a judgement about what’s fundamentally in our interest, and that’s how he’s proceeded.”

He added that the administration has supplied critical humanitarian aid and military equipment, and continues to do so, including another $800 million in security aid Biden announced Wednesday. Republicans have argued he could take other steps, including by providing MiG fighter jets Ukraine has sought.

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“When it comes to the things that are making the Ukrainians most effective in dealing with this onslaught from Russia, we’ve been providing it,” Blinken said, pointing to anti-armor and air defense systems.

“Virtually everything going on on the ground in Ukraine is not going according to Putin’s plan,” he said.

He also said that the refugee crisis prompted by Russia’s onslaught could eventually see Ukrainians fleeing to the U.S., but that for now most are choosing to remain in Europe, near their country and families.

“Given the numbers that we’re looking at, there is almost certainly going to be an interest, a demand, on countries far from Europe including the United States, to take people in,” Blinken said. For now, though, he said “we’re focused on helping countries that are already taking in refugees.”

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