LIVE - Updated at 08:01
UK Ministry of Defence says Russia may be trying to draw in or fix additional Ukrainian forces.
Russia has probably increased the intensity of its attacks in the Donetsk area of eastern Ukraine's Donbas region over the past five days, according to British intelligence.
Pro-Russia separatists have most likely made progress towards the centre of Pisky village, near Donetsk airport, but Russian forces overall had secured few territorial gains, the latest report from the UK Ministry of Defence says.
It adds:
There is a realistic possibility that Russia has increased its efforts in the Donbas in an attempt to draw in or fix additional Ukrainian units, amid speculation that Ukraine is planning a major counter-offensive.
Latest Defence Intelligence update on the situation in Ukraine - 27 August 2022
Find out more about the UK government's response: https://t.co/kLlYq5lRT2
???? #StandWithUkraine ???? pic.twitter.com/JZ4eHkfH6t
Nato's secretary general, Jens Stoltenberg, stressed the need to boost security along the alliance's northern flank to counter Russia, as he concluded a visit to Canada that included a tour of its Arctic defences.
"The high north is strategically important for Euro-Atlantic security," Agence France Presse reported Stoltenberg as telling a news conference at an air base in Alberta. With Finland and Sweden joining Nato, he noted, seven of eight Arctic states would be members.
Referring to the North American aerospace defence command (Norad), a US-Canadian organisation, Stoltenberg said:
The shortest path to North America for Russian missiles and bombers would be over the North Pole. This makes Norad's role vital for North America and therefore also for Nato.
Stoltenberg said Russia's capabilities in the far north "are a strategic challenge for the whole alliance", citing a significant Russian military buildup in the region. That included the reopening of "hundreds of new and former Soviet era Arctic military sites" and its use of the high north "as a testbed for the most advanced weapons including hypersonic missiles".
The Nato chief also expressed concerns about China's reach into the Arctic for shipping and resources exploration, with plans to build the world's largest icebreaker fleet.
Beijing and Moscow have pledged to intensify practical cooperation in the Arctic. This forms part of the deepening strategic partnership that challenges our values and our interests.
The governor of the Donetsk region says three-quarters of its population has been evacuated amid Russian assaults in Ukraine's east.
Pavlo Kyrylenko told Ukrainian TV:
There is practically not a single major town or city that is not subject to [Russian] shelling.
Reuters also reported the Ukrainian military general staff as saying Russian aircraft had attacked several sites and was focusing on more than a dozen towns in the south, including Mykolaiv near the Black Sea.
There were also air strikes against several towns in the Sumy region near the Russian border, the general staff said, and Russian forces had shelled and carried out air attacks against the Kharkiv region in the north-east.
Also on Friday, Washington confirmed reports that a US citizen had recently died in Ukraine, but declined to provide further details.
Ukraine suspects Moscow intends to divert power from the Zaporizhzhia nuclear power plant to the Crimean peninsula, which was annexed by Russian troops in 2014.
Washington warned on Thursday against such a move, with State Department spokesman Vedant Patel saying attempts to redirect power to occupied areas were "unacceptable".
The electricity that it produces rightly belongs to Ukraine.
Agence France-Presse also reported that Britain's defence ministry said satellite imagery showed an increased presence of Russian troops at the occupied power plant in south-eastern Ukraine, with armoured personnel carriers deployed within 60m (200 feet) of one reactor.
Hello and welcome back to the Guardian's continuing live coverage of the war in Ukraine. I'm Adam Fulton and here are the latest developments as it has just passed 9am in Kyiv on this Saturday 27 August 2022.
The Ukrainian president, Volodymyr Zelenskiy, said the situation at the Zaporizhzhia nuclear power plant remained "very risky" after two of its six reactors were reconnected to the grid following shelling that caused Europe's largest nuclear power plant to be disconnected for the first time in its history. "Let me stress that the situation remains very risky and dangerous," he said in his regular evening address on Friday, praising Ukrainian experts working to "avert the worst-case scenario".
Residents near the Zaporizhzhia plant have reportedly been given iodine tablets amid mounting fears that the fighting around the Russian-occupied complex in south-eastern Ukraine could trigger a catastrophe.
Zelenskiy said the world narrowly avoided a "radiation disaster" on Thursday when electricity to the Zaporizhzhia plant was cut for hours after fires broke out around it.
A team of inspectors from the United Nations nuclear watchdog are poised to make an emergency visit to the Zaporizhzhia plant, according to reports. Sources have told the Wall Street Journal it is "almost certain" that a mission from the International Atomic Energy Agency will visit the plant early next week, although details are still being completed.
Ukraine's deputy prime minister, Iryna Vereshchuk, has announced plans to expand mandatory evacuations for civilians living on the war's frontlines. Speaking on national television, she said evacuating women with children and elderly people would be a priority from some districts of the eastern Kharkiv region, and the southern Zaporizhzhia and Mykolaiv regions.
Ukrainian forces have struck an important bridge used by Russian occupying forces in the southern Kherson region, according to Ukraine's southern military command. The Daryivskiy Bridge is the only Russian-controlled crossing across the Inhulets river, which splits the Russian-occupied land west of the Dnipro into two parts.
Former Russian president Dmitry Medvedev, an ally of President Vladimir Putin, said in a French television interview on Friday that Russia was prepared to hold talks with Volodymyr Zelenskiy subject to certain conditions, but warned Moscow would not stop its assault until its goals had been achieved. "Renouncing [Ukraine's] participation in the North Atlantic alliance is now vital, but it is already insufficient in order to establish peace," Medvedev told LCI television in quotes reported by Russian news agencies.
EU energy ministers will gather for an urgent meeting as soon as possible to discuss the energy crisis following Russia's invasion of Ukraine, the Czech prime minister said. The Czech Republic currently holds the presidency of the European Council.
Russia's claim that it is deliberately slowing the pace of its military campaign in Ukraine is "almost certainly deliberate misinformation", according to British intelligence. The latest UK Ministry of Defence report said Russia's offensive had stalled "because of poor Russian military performance and fierce Ukrainian resistance".
The Belarusian president has said his country's SU-24 warplanes have been re-fitted to carry nuclear armaments. Alexander Lukashenko said he had previously agreed to the move with his Russian counterpart, Putin, and warned that his country was ready to respond to "serious provocation" from the west instantly.
Russia is burning off large amounts of natural gas that it would previously have exported to Germany while energy costs soar in Europe, the BBC has reported. According to the broadcaster, which cites an analysis by Rystad Energy, a plant near Russia's border with Finland is burning an estimated £8.4m worth of gas every day.
The head of the UK's energy regulator, Ofgem, has blamed Russia for driving up energy prices, resulting in the UK price cap rising by 80%. Ofgem on Friday approved a £1,578 increase on the current price cap of £1,971 for the average dual-fuel tariff.
The German ambassador to the UK has acknowledged there is a risk public support for Ukraine could wane this winter as the energy crisis intensifies. Putin was "using gas as a weapon" in the UK and all of Europe, Miguel Berger said. "He wants to test our resolve."