Kyiv, Ukraine(CNN) Ukrainian President Volodymyr Zelensky has urged US counterpart Joe Biden to deliver a strong and "useful" message about the Russian invasion at his State of the Union speech on Tuesday, in an exclusive interview with CNN and Reuters from the bunker in Kyiv in which he is leading his military's response.
In the rare interview on Tuesday afternoon, Zelensky said that as long as Moscow's attacks on Ukrainian cities continued, little progress could be made in talks between the two nations.
"You have to speak first of all. Everybody has to stop fighting and to go [back] to that point from where it began five, six days ago," Zelensky said. "It's important to stop bombing people and then we can move on and sit at the negotiation table."
Asked if he felt Ukraine was wasting its time by talking with Russia, he said: "We'll see." Officials from the two countries met for the first time on Monday since Russia's invasion began last week.
Ahead of Biden's speech in Congress on Tuesday, Zelensky urged the President to impress upon Americans the urgency and implications of Russia's invasion.
"He is one of the leaders of the world and it is very important that the people of the United States understand (that) despite the fact that the war is in Ukraine ... it is [a] war for the values of democracy, freedom," Zelensky said.
Zelensky reiterated calls for the US and NATO to establish a no-fly zone over Ukraine or put boots on the ground. "I've already addressed and (spoken) to some Western leaders with this request, because I do believe that leaders do have to support democratic countries and they have to help them."
"When we talk about no-fly (zones), we're looking back into history ... and that doesn't mean that we need to draw another country into the war. And, frankly, you know, everyone is drawn into the war now."
"I've spoken to Biden many times," Zelensky said. "And I've told them many times that Ukraine will resist and fight stronger than anyone else but on our own against Russia we won't manage it."
"That's why if somebody wants to help us, everybody has to act swiftly," Zelensky added. "This is the moment."
The US and NATO allies have aided Ukraine by sharing arms, military equipment and intelligence, while also imposing dramatic sanctions on Russia. But the alliance has thus far made clear it has no plans to send soldiers into Ukraine, which is not a NATO member.
Zelensky also predicted troubles in NATO member states if Russia seizes control of his country. "If Ukraine fails, then all these troops will be at your borders, Poland, Lithuania ... and you'll be facing greater issues. There'll be other provocations there," he said.
As CNN and Reuters met with Zelensky inside his Kyiv bunker, the capital -- along with cities across Ukraine -- braced for a renewed and intensified assault by Russian forces.
Rockets were fired near a TV tower on Tuesday afternoon, hours after Russia warned of "high-precision" strikes on other facilities linked to Ukrainian security agencies. The rocket attack took out broadcasting hardware, raising fears that Russia is attempting to knock out the city's communications infrastructure, Ukraine's Ministry of Internal Affairs said.
Zelensky told CNN on Tuesday that Russia was indiscriminately attacking Ukrainian citizens and historical landmarks.
"As you can see, no one is being very careful about the targets. We see the children are being killed ... We are defending our right for life," he said, adding that Moscow is "launching their missiles against the ancient old Kyiv, the heart of Kyiv."
He spoke triumphantly of Ukraine's resistance, and said of Russian soldiers: "They have no idea what they [are] doing. They don't know our streets. They don't know this people. They don't understand our philosophy. Our mentality, our aspirations, what kind of people here they have, they know nothing.
"They're just sent to kill and die," Zelensky said.
As the rockets hit Kyiv on Tuesday, a 40-mile Russian convoy of tanks, armored vehicles and towed artillery was headed toward the Ukrainian capital, according to satellite images from Maxar Technologies, while the military beefed up its attacks on other key cities.
Attacks have also hit Ukraine's second city, Kharkiv. More than 20 people were injured, including a child, in an explosion at a government building there, Ukraine's State Emergency Service said in a Telegram post Tuesday.
Russia's actions on Tuesday mark a far less restrained bombing campaign, raising concerns that more civilians could be hit in strikes. The UN says that at least 102 civilians have been killed across the country and 304 injured, though those figures are likely to underestimate the true toll.
Zelensky has drawn global praise for his response to the invasion, having refused offers to evacuate and instead delivering frequent messages to Ukrainians as Kyiv comes under Russian assault.
Earlier on Tuesday he received a standing ovation for an emotional address to the European Parliament via video link, telling delegates: "We are fighting for our life."
Asked by CNN about his transformation from comic actor to world-famous wartime leader, Zelensky responded: "It's very serious, it's not a movie ... I'm not iconic, I think Ukraine is iconic."
"Ukraine is the heart of Europe, and now I think Europe sees Ukraine is something special for this world," he added. "That's why [the] world can't lose this something special."
The Ukrainian leader appeared tired and stressed but was friendly with crews from CNN and Reuters. He said he hadn't seen his family for three days; asked what his typical days are like, he said: "Work and sleep."