Russian military vehicles and special forces on Sunday entered the Ukrainian city of Kharkiv, the second largest city in the country.
Reports of heavy fighting in Kharkiv continue following the Russian entry into the city.
Andrei Baklikov, an Israeli-Ukrainian citizen who is fighting in Kyiv, told Galai Tzahal (IDF Radio) that the citizens of Ukraine do not intend to lay down their arms and will fight against the Russian army forces that will arrive in the city.
"We have no organized positions. If a Russian force arrives in the city, we will fight against it. The army is assisted by local volunteer forces, each squad has a commander and it is actually like a military body. Anyone who can and wants to fight gets a weapon," Baklikov said.
"Ukraine is home," he said. "The war started eight years ago, it's good that they remembered now to impose sanctions. I want Ukraine to continue the trend of development - the economy is stabilizing, corruption is slowly disappearing. I want Putin to give up, we need people who know how to fight."
Dima, a resident of Kyiv, told Reshet Bet that "Kyiv is ready for defense, there are tens of thousands of people here with weapons who are not willing to give up. It is a big and complicated city in terms of construction, it has a river - it could be hell for the Russian army."
Google announced overnight that it intends to prevent the display of and ads sponsored by Russian state media outlets as part of its services.
A six-year-old boy was killed and several civilians were injured by heavy gunfire in the western district of Kyiv, CNN reported on Saturday night, quoting the local hospital in the Ukrainian capital.
According to the report, two teenagers were among those injured.
In another incident, Russian soldiers blew up a natural gas pipeline in the city of Kharkiv.
The Ukrainian government subsequently warned that the smoke from the blast could cause an "environmental catastrophe" and advised residents in the area to cover their windows with damp cloths.
Earlier, two explosions were reported in the city of Vasylkiv, south of Kyiv, near the area where the Ukrainian Air Force Central Command is located. According to reports, an oil depot exploded after being hit by a missile.
Meanwhile, a senior US official toldABC News on Saturday that some Russian forces taking part in the invasion of Ukraine are disoriented, realizing the battles against Ukrainians are harder than they thought.