Russian President Vladimir Putin is intensifying his assault on Ukraine, despite previously signaling to President Donald Trump that peace might be on the table.But one former Trump advisor says Putins strategy is unlikely to succeed."I dont think he can play Donald Trump," retired Gen. H.R. McMaster, who served as Trumps national security advisor from 2017 to 2018, told "The Brian Kilmeade Show" on Wednesday."You saw what happened with the Iranians. He gave them 60 days, right? And they went to 61, and he acted."PENTAGON'S WEAPONS PAUSE TO UKRAINE COULD ENCOURAGE AND ESCALATE PUTINS WAR AMBITIONS: SECURITY EXPERTSRussia launched its largest aerial strike on Ukraine since the start of the war this week, marking an escalation in the conflict. McMaster said this is part of a calculated attempt by Putin to project power and reshape his image."This is Putins ruse. Hes trying to look strong," McMaster told the "Brian Kilmeade Show.""Hes throwing it all in right now because he thinks we dont have the will to support Ukraine."SEN LINDSEY GRAHAM: RUSSIA SANCTIONS BILL AIMS TO CHANGE PUTIN'S CALCULUS, PROTECT WORLD ORDERSEN. JEANNE SHAHEEN: IF TRUMP WANTS A UKRAINE DEAL, HE SHOULD REREAD HIS OWN BOOKThe increase in Russian aggression comes as the Pentagon has paused some weapons shipments to Ukraine. The scrapped deals included Patriot missile interceptors and artillery shells. U.S. officials have justified the delay by blaming it on dwindling stockpiles and concerns the United States could need them to defend itself.While Putin is projecting strength, McMaster argued the Russian leader is far weaker than he appears."Putin is really in a hurt, in terms of his economic situation," he said. "Hes not pulling as much out of the ATM as hes been able to pull," noting that declining oil prices and skyrocketing military expenses have taken a toll on Russias economy.According to McMaster, these developments could push Trump to take a firmer stance if peace talks continue to falter."President Trump is [going to] come to the conclusion its time to put more pressure on Putin, and that includes sustaining support for the Ukrainians."Last month, Trump proposed taking a step back in ceasefire negotiations, likening Russia and Ukraine to two children fighting. He suggested the U.S. take a step back in negotiations until both countries are willing to come to the table."Sometimes you're better off letting them fight for a while and then pulling them apart," remarked Trump in early June.TRUMP INSISTS UKRAINE-RUSSIA PEACE DEAL IS CLOSE, BUT MISTRUST IN PUTIN LEAVES EXPERTS SKEPTICALSome leaders have countered the presidents strategy, saying U.S. support is critical to the Ukrainian resistance. On Wednesday, NATO Secretary General Mark Rutte emphasized that Ukraine cannot win without American aid."A secure Europe also means a secure U.S.," Rutte told "Fox & Friends." The Dutch leader also noted that a larger Russia thats closer to Europe could pose more of a risk to U.S. interests.CLICK HERE TO GET THE FOX NEWS APP