Following a weekend visit to Ukraine, Maine Sen. Susan Collins said in an interview Tuesday she supports more military and humanitarian aid for the war-ravaged country.Collins, a member of the Senate’s Intelligence and Appropriations Committees who is serving her fifth term in office, was one of four high-ranking Republicans to visit Kyiv over the weekend, along with Senate Minority Leader Mitch McConnell, of Kentucky, Republican Conference Chair John Barrasso, of Wyoming, and John Cornyn, of Texas. The group met with Ukrainian President Volodymyr Zelenskyy, in Kyiv, for a two-hour lunch.RELATED: Extended interview with Sen. Susan Collins“I am so impressed and inspired by him,” Collins said. “To meet him in person only reinforced the impression of a strong leader who has united his people against this brutal Russian aggression that is completely unjustified.”Collins said Zelenskyy asked for more weapons to fight Russian troops who began their invasion almost three months ago.Collins said, “He explained the challenge of needing more heavy artillery and weapons, like the Neptune weapons, which they used to take out the flagship of the Russian fleet."Congress is expected to approve a new $40 billion aid package for Ukraine this week. Collins said, “We talked about the ports. I asked him, because I’m aware they need to need to ship their grain out to prevent hunger in parts of the world and also to bring the income to the Ukrainian economy.”McConnell described the aid as ‘tools for self-defense,’ and Collins said aid that has stopped short of deploying troops appears to be helping thwart the aims of Russian President Vladimir Putin.Collins said, “Putin’s invasion has produced exactly the opposite result of what he wanted. He claimed to invade Ukraine, because it was getting too close to the West, then he thought he would be greeted enthusiastically. Instead, his invasion and brutal tactics have caused even the Russian portions of Ukraine to embrace their Ukrainian identity.”Collins said the evidence of Russian atrocities against civilians is mounting. "The deliberate bombing of a maternity hospital, health clinics, schools, shelters, refugees that are trying to evacuate and who were promised safe passage," Collins said. "So, I hope Putin will be considered a war criminal."Collins said the Biden administration should consider listing Russia as a state sponsor of terrorism, as Zelensky requested.She also said the Republicans’ visit, following the recent trip of Democratic House Speaker Nancy Pelosi, underscored the bipartisan support for additional aid.After leaving Ukraine, the senate delegation traveled to Helsinki, where they met leaders of Finland, which shares an 835-mile border with Russia, and to Stockholm to meet Swedish leaders.Collins supports their applications to join the U.S.-led, 30-nation, NATO military alliance, whose central tenet is an attack on one nation is an attack on all.Collins said, “Both of them will add a lot to the Western defensive alliance. The Finns, in particular, have a very strong and capable military, and both countries are experts with technology and are relatively wealthy countries” who can afford to allocate at least 2% of their gross domestic product to military spending, as the alliance requires.Collins said, "Sweden's been neutral for 200 years. But as the Swedish prime minister said, Feb. 24, the day that Russia invaded Ukraine, changed everything for them."Since Collins’ visit to nations neighboring Ukraine, in March, the refugee crisis has gotten worse.Collins said, “More than three million Ukrainians have left the country, and about seven to eight million are displaced internally, because their homes have been bombed, or there’s no infrastructure, there’s no water, there’s no electricity, and so, they are enduring tremendous hardship.”