Ukrainian forces have pushed back Russian troops in several areas around Kyiv, city mayor Vitali Klitschko has said, vowing to defend every building rather than surrender the capital.
Mr Klitschko said there were battles raging on the northern and eastern outskirts of the city, and that "the small city of Makariv and almost all of Irpin is already under the control of Ukrainian soldiers".
Irpin borders Kyiv to the east, and Makariv is located some 50km to the west.
Fierce exchanges of artillery fire have taken place in Irpin and Lyutizh to the north of Kyiv, with considerable activity behind the frontlines in Irpin.
A Ukrainian news agency spoke of a possible encirclement of Russian troops at Irpin, as well as Bucha and Hostomel, which are located in the western outskirts of Kyiv.
Mr Klitschko said he did not have any more detailed information of ongoing Ukrainian counteroffensives.
Russian troops quickly pushed to the outskirts of Kyiv after invading the country on 24 February, but their attempts to encircle and enter the city have failed.
The "target of aggressors is the capital of Ukraine ... because the city is the heart of the country," former boxing champion Klitschko told a news conference in a city park overlooking the Dnipro river.
He urged Russian soldiers to go back home and said Ukrainians are ready to defend Kyiv building by building.
"We would rather die than kneel in front of the Russians or surrender to the invaders," he said.
"We are ready to fight for each building, each street, every part of our city."
A residential neighbourhood in northwestern Kyiv came under bombardment this morning, with several buildings damaged and four people wounded.
A toll kept by city authorities puts the civilian death toll in the capital at 73, including four children, since the start of the invasion. Another 297 people have been wounded.
The Ukrainian capital has been under curfew since the beginning of the week. Mr Klitschko said the measure was necessary because of information from the military about possible attacks.
He said dozens of saboteurs had been arrested since the start of the conflict.
his funeral in Kyiv, alongside his 11-year-old son
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German Chancellor Olaf Scholz has said Russia's invasion of Ukraine has stalled despite the daily assaults, and urged Moscow to "immediately" stop the fighting.
"Putin's offensive is stuck despite all the destruction that it is bringing day after day," Mr Scholz said in a speech to the German parliament.
Unprecedented sanctions imposed by Western partners are working and will only bring further damage to Russia's economy, the German leader warned.
"But that is just the beginning, many of the toughest consequences will only been seen in the coming weeks," he said, warning that "we are constantly creating sanctions."
Vladimir Putin "must hear the truth" that not only is the war destroying Ukraine, "but also Russia's future".
In an interview with weekly Die Zeit, Mr Scholz said he had an "idea about an outcome for talks" on an end to the Russian invasion, but said to discuss it publicly would be "irresponsible".
"The admirable resistance of Ukrainians has increased the chances of a deal" between Moscow and Kyiv, he said.
"But it is far from certain. It is still unclear whether Russia even wants an agreement. That's how bitter the situation is."
Meanwhile, a veteran Kremlin envoy has resigned and left Russia with no intention to return, a source said, the first senior official reported to have quit since Russia launched its invasion of Ukraine a month ago.
Anatoly Chubais was one of the principal architects of Boris Yeltsin's economic reforms of the 1990s and held senior business and political roles under Putin. He had been Putin's special envoy to international organisations since 2020.
It comes as US President Joe Biden flies to Europe for an emergency NATO summit on Ukraine, where invading Russian troops are stalled, cities are under bombardment and the besieged port of Mariupol is in flames.
Four weeks into a war that has driven a quarter of Ukraine's 44 million people from their homes, Russia has failed to capture a single major Ukrainian city, while Western sanctions have ostracised it from the world economy.
After failing in what Western countries say was an attempt to seize Kyiv and depose the government, Russian forces have taken heavy losses, been frozen in place for at least a week on most fronts and face supply problems and fierce resistance.
They have turned to siege tactics and bombardment of cities, causing massive destruction and many civilian deaths.
Moscow says its aim is to disarm its neighbour, and its "special military operation" is going to plan. It denies targeting civilians.
Worst hit has been Mariupol, a southern port completely surrounded by Russian forces, where hundreds of thousands of people have been sheltering since the war's early days, under constant bombardment and with food, water and heat supplies cut.
New satellite photographs from commercial firm Maxar released overnight showed massive destruction of what was once a city of 400,000 people, with columns of smoke rising from residential apartment buildings in flames.
No journalists have been able to report from inside the Ukrainian-held parts of the city for more than a week, during which time Ukrainian officials say Russia has bombed a theatre and an art school used as bomb shelters, burying hundreds of people. Russia denies targeting those buildings.
Mr Biden, due to arrive in Brussels this evening, will meet NATO and European leaders in an emergency summit at the Western military alliance's headquarters.
The leaders are expected to roll out additional sanctions against Russia tomorrow.
In a sign of Moscow's further isolation, Poland announced it was expelling 45 Russian diplomats accused of either being undercover spies or "associated" with them. Several other eastern European countries have announced similar moves in recent days, although not on such a large scale.
Russia has rejected all the accusations.
Despite its losses so far, Russia may still be hoping to make more gains on the battlefield, especially in the east, in territory including Mariupol which Moscow demands Ukraine cede to Russian-backed separatists.
In a daily intelligence update, Britain's defence ministry said the entire battlefield across northern Ukraine - which includes huge armoured columns that once bore down on Kyiv - was now "static", with invaders apparently trying to reorganise.
But in the east, the Russians were trying to link troops at Mariupol with those near Kharkiv in the hope of encircling Ukrainian forces, while in the southwest they were bypassing the city of Mykolayiv to try to advance on Odesa, Ukraine's biggest port.
Ukrainian officials described sporadic shelling in other cities overnight, with two civilians killed in the Mykolayiv region, a bridge destroyed in the Chernihiv region, and residential buildings and a shopping mall struck in two districts of Kyiv, wounding at least four people.
