Russian President Vladimir Putin may have ordered Russian forces to seize the city of Kharkiv and the rest of the unoccupied Kharkiv region despite the extreme improbability of success, according to the US-based Institute for the Study of War (ISW) research group.

However, in its daily report, ISW said it was offering the observation as a hypothesis rather than an assessment as it was based on "limited and circumstantial" indicators.

Russian forces have tried to take the town of Dementiivka, to the north of Kharkiv city, in recent weeks even though it has limited significance for defending Russian territory.

In addition, Ukrainian intelligence released an intercepted conversation on Saturday in which a Russian soldier stated that his commander cares nothing for his losses and only wants to reach Kharkiv.

A previous ISW report said Russian-backed authorities in occupied parts of the Kharkiv region have stated that the area is an "inalienable part of Russian land."

Pro-Moscow officials there unveiled a new flag for the occupation regime, which contains the Russian imperial double-headed eagle and symbols from the 18th century Kharkiv coat of arms.

The occupied administration has also signed a mutual defense pact with separatists in Luhansk, indicating that they are not planning to leave. Statements from the administration have indicated it aims to control areas of the region currently under Ukrainian control.

Even in 2014, as fighting rumbled in the neighboring Luhansk and Donetsk regions, there were fears that Kharkiv might be next.

Kharkiv city has been heavily bombed and was the scene of some of the bloodiest fighting of the war until Russian troops withdrew from around it as Moscow focused on its war in Donbas.

Bombardments of the area have been fast and hard in recent days.

The report said Russian forces would probably intensify ground assault attempts north of Kharkiv city over the coming days "but are unlikely to secure significant territorial gains."

Here are the other main headlines from the war in Ukraine on Sunday, July 17.

Ukraine 'will never accept' Canada's decision on Nord Stream turbine

Ukrainian President Volodymyr Zelenskyy said he had told Canadian Prime Minister Justin Trudeau on Sunday that Ukrainians would never accept Canada’s decision regarding the Nord Stream 1 gas turbine.

Canada had recently decided to return the turbine to Germany, citing the "very significant hardship" that the German economy would suffer without a sufficient gas supply.

Zelenskyy said in his nightly video address that he had talked to Trudeau earlier and thanked him for his support. "However I stressed separately that Ukrainians will never accept Canada's decision regarding the Nord Stream urbine," he said. Handing it to Germany violated sanctions, he added.

The Nord Stream 1 pipeline runs under the Baltic Sea from Russia to Germany. It is Germany's main source of Russian gas. Gas is usually sent onward to other countries, as well.

It is currently shut down for annual maintenance.

There are concerns in Germany that Russia may not resume the flow of gas as scheduled from July 21.

UK says Russian forces digging in

The UK's Ministry of Defence says Russia is reinforcing its defensive positions across the occupied areas of the south of Ukraine, apparently in response to recent attacks, and possible future ones as Kyiv's forces seek to regain lost territory.

Moscow has been moving manpower, equipment, and defensive stores between Mariupol and Zaporizhia, and in Kherson.

"Russian defensive moves are likely a response to anticipated Ukrainian offensives, to demands made by Defence Minister Shoygu on a recent visit to the Donbas, and also to the attacks Ukraine is launching against command posts, logistic nodes and troop concentrations," the report said. "Given the pressures on Russian manpower, the reinforcement of the South whilst the fight for the Donbas continues likely indicates the seriousness with which Russian commanders view the threat."

UK military chief: Putin health rumors 'wishful thinking'

Admiral Tony Radakin, the head of the UK's armed forces, said speculation and rumors around the state of Russian President Vladimir Putin's health is a matter of "wishful thinking."

Radakin told the BBC, "As military professionals we see a relatively stable regime in Russia. President Putin has been able to quash any opposition, we see a hierarchy that is invested in President Putin and so nobody at the top has got the motivation to challenge President Putin,"

Radakin added, "And that is bleak."

He noted the land forces may pose less threat now since the war has taken out an estimated 50,000 Russian soldiers who are either killed or wounded. An estimated 1,700 Russian tanks have been destroyed along with 4,000 armored fighting vehicles.

Russia strikes south Ukraine city

The mayor of the southern Ukrainian city of Mykolaiv, Oleksandr Senkevych, says Russian missiles struck a key shipbuilding center in the estuary of the Southern Bug river. There was no immediate information about casualties.

Mykolaiv has been hit by regular Russian missile strikes in recent weeks as the Russians try to weaken Ukrainian defenses.

The Russian military has said it aims to take over Ukraine's entire Black Sea coast all the way to the Romanian border. Such an effort would deal a crushing blow to the Ukrainian economy and trade and give Moscow a land bridge to Moldova's separatist region of Transnistria, where Russia has a military base.

Ukrainian forces fended off Russian attempts to capture Mykolaiv, which sits between Russia-occupied Crimea and the main Ukrainian port of Odesa, early in the campaign.

Russian troops have halted their attempts to advance in the city since then, but have continued to hit both Mykolaiv and Odesa with regular missile strikes.

Zelenskyy dismisses head of state security, prosecutor general

Ukrainian President Volodymyr Zelenskyy issued an executive order dismissing the head of the country's state security service, Ivan Bakanov, as well as prosecutor general Iryna Venediktova.

The announcement was made via a statement on the website of the president's office.

Zelenskyy said in a separate Telegram post that the two senior officials had been fired due to the number of cases of collaboration with Russia from within their agencies. 

He noted 651 treason and collaboration cases had been opened against prosecutorial and law enforcement officials, with sixty such cases coming from the state security service and the office of the prosecutor general in Russian-occupied territories.

Oleksiy Symonenko was named the new prosecutor general in a separate decree.

Girl, 4, buried after Vinnytsia missile strike

Liza Dmytrieva, 4, was buried after she was killed in a Russian missile strike last week in the central Ukrainian city of Vinnytsia far from the frontline. Liza, who has Downs syndrome, was with her mother on their way to her speech therapist when a Russian missile struck Thursday. 

At least 23 others were killed, including two other children, boys ages 7 and 8. Two hundred were wounded, including Liza's mother who remains in intensive care In grave condition.

At the funeral, an Orthodox priest burst into tears and told Liza's family, "Evil cannot win."

EU highlights anniversary of MH17 downing

The European Union has marked the eighth anniversary of the downing of Malaysian Airlines Flight MH17 in eastern Ukraine, reiterating its full support for all efforts to seek justice for the 298 victims.

Four pro-Russian separatists are on trial, in absentia, in the Netherlands, accused of bringing down the Boeing 777 flying from Amsterdam to Kuala Lumpur on July 17, 2014.

International investigators found that the plane was shot down by a Russian Buk surface-to-air missile.

"Russia's war of aggression against Ukraine is a painful reminder of what happened eight years ago to the 298 people on board Flight MH17 and it strengthens the need to establish accountability," a statement from the EU said.

"Recalling its previous statements, the European Union takes note of all legal proceedings that are taking place in this regard and expects Russia to accept its responsibility and to fully cooperate with efforts to establish accountability."

EU to pass more sanctions on Russia

The European Union will discuss tightening sanctions against Russia on Monday.

With the conflict grinding on and increasingly spilling out into global energy and food crises, the bloc's foreign ministers are considering banning gold purchases from Russia, something that would align with sanctions already imposed by G7 partners. More Russian individuals could also be placed on the EU's blacklist.

"Moscow must continue to pay a high price for its aggression," European Commission President Ursula von der Leyen said after forwarding the proposed measures.

Catch up on DW's Ukraine content

German Chancellor Olaf Scholz says a decision to fire up coal and oil power plants again — to cushion the impact of energy shortages because of Russia's war in Ukraine — is only temporary. 

DW looks at the issues facing Germany when it comes to the power supply.

After orders to step up operations in Ukraine, Russian forces appear to be resuming their attacks in the Donbas region with small-scale offensives near the city of Sloviansk. 

Read this and more of our updates from Saturday.

ar, rc/kb, sms (dpa, Reuters, AP, AFP)