Ukrainian President Volodymyr Zelensky's chief of staff has said that using western weapons to strike inside Russia is a vital decision that will impact Moscow's tactical aviation and its capability to operate in border areas.
Following pressure from Ukraine and some of its European allies, the United States agreed last week to change its policy and allow Kyiv to strike inside Russia with western weapons as part of its campaign to repel the Russian invasion.
Ukraine said the move would help push back Russia's advances and better defend territory in the northeast Kharkiv region.
"Permission to use western weapons on the territory of the Russian Federation is a vital decision," Andriy Yermak said on social media.
"This will impact the conduct of the war, planning of counteroffensive actions, and will weaken Russians' abilities to use their forces in the border areas."
The decision will also help to better fend off Russian aerial attacks, Mr Yermak said.
Ukraine has frequently targeted occupied Crimea, which Russia annexed in 2014, with western-made weapons.
But outgunned and outmanned on the battlefield, Kyiv had pleaded with the US to allow it to strike targets on Russian soil with American-made weapons, as Moscow launched a new front in Kharkiv.
The city - Ukraine's second largest with about 1.3 million people - is about 30km from the Russian border.
US administration officials said the latest decision was narrowly tailored to the battle in the Kharkiv region.
They said it allows Ukraine to use US-supplied weapons to fire back against Russian forces "attacking them or preparing to attack them" from across the border.
Kyiv is also trying to develop its own weapons - mainly focusing on drones - to hit targets inside Russia.
Some Ukrainian drones have attacked Russian oil facilities and military targets hundreds of kilometres away from the border.
One of the deepest attempted drone strikes was an attack on a long-range radar station in the city of Orsk, which is 1,800km from the frontier.
Eight hurt in Russian missile strikes
Ukrainian officials said that eight people had been wounded in overnight Russian air attacks on the Dnipro and Kharkiv regions.
Russian forces also launched four drones. The Ukrainian air force said it shot down two of them over the northern region of Chernihiv.
The head of the southern Kherson region, which Russia claims is part of its country, separately said that Russian artillery fire had killed an elderly woman in the village of Veletynske.
Ukrainian officials have repeatedly emphasised the urgent need for air defence systems as Russia has pummelled the country with air strikes targeting critical infrastructure this spring.
Kyiv has confirmed that Italy will supply it with another air defence system.
Western army trainers in Ukraine not immune from attack - Russia
Western army instructors who train Ukrainian soldiers in the country would have no "immunity" from Russian strikes, Moscow has said, amid reports that France could despatch military trainers to Ukraine.
Last week, Ukrainian army chief Oleksandr Syrsky said that French military instructors would soon arrive in the country, but Kyiv's defence ministry later downplayed the claim.
"Any instructors who are engaged in training the Ukrainian regime do not have any immunity. It does not matter whether they are French or not," Russian government spokesman Dmitry Peskov said.
French President Emmanuel Macron has refused to rule out deploying troops to Ukraine, despite reluctance from other NATO members and warnings from Moscow.
France does not officially have military personnel assisting or training Ukrainian forces in Ukraine.
Russia has warned against such a step, and previously said it would destroy any western military hardware sent to the country.
Ukraine's defence minister said it is still in talks with France and other allies on the issue of instructors.
Russia 'doesn't interfere' in France after Eiffel Tower coffin stunt
The Russian Embassy in France said it does not interfere in the country and condemned "Russophobic" suggestions that Moscow was involved in coffins laid at the Eiffel Tower in Paris marked "French soldiers serving in Ukraine".
In a statement, the embassy said it "expresses a decisive protest against the latest Russophobic campaign unleashed by French media".
"Russia has not interfered and does not interfere in France's internal affairs," it added.
Moscow, meanwhile, dismissed a report from Microsoft that Russia was ramping up a disinformation campaign ahead of the Olympics Games, calling it "absolute slander" and "nothing to do with reality".
