Kiev ( Ukraine ) (AFP) - The European Union is discussing tougher sanctions against Moscow on Monday for its invasion of Ukraine, as President Volodymyr Zelensky sacked the chief prosecutor and head of the security services over suspicions of several cases of treason committed by local officials on behalf of the Russians.

Arriving at the Brussels meeting, the EU foreign policy chief declared that resuming grain exports from Ukraine was a "matter of life and death" and there was "hope" for a deal this week to open the port of Odessa.

Borrell said that "the lives of (...) tens of thousands of people depend on this agreement," which is being negotiated between Russia, Ukraine, Turkey and the United Nations and aims to remove about 20 million tons of grain stuck in Ukrainian silos due to the attack launched by Moscow, through the Black Sea.

The European Union intends to continue its pressure on Moscow by imposing new sanctions on the one hand and providing financial and military support to Ukraine on the other, according to Borrell.

It is scheduled that the foreign ministers of the European Union countries will consider two proposals by the European Commission to prevent the purchase of gold from Russia in order to align European sanctions with those imposed by its partners in the Group of Seven, and to include new Russian personalities on the union’s blacklist.

Ukrainian Foreign Minister Dmytro Kuleba warned his European counterparts during Monday's meeting against any attempt to ease their sanctions on Russia or submit to the demands of Russian President Vladimir Putin. "Undoing (the sanctions) or yielding to his demands will not work. It never worked. It is a trap," he said.

The successive measures adopted by the Union so far isolated Russia and hit it economically, but did not make it back down or stop its attack on Ukraine that began on February 24.

And the President of the European Commission, Ursula von der Leyen, during a visit to Azerbaijan, announced an agreement with this former Soviet republic located in the Caucasus, to double the European Union's imports of Azerbaijani gas "within a few years."

At a time when Russia continues its bombing of many Ukrainian cities, President Zelensky announced on Sunday evening that he had taken "a decision to relieve the Prosecutor (Irina Venediktova) and the head of the security services (Ivan Bakanov)" from their duties.

He pointed out that the Ukrainian authorities are currently investigating more than 650 suspected cases of treason committed by local officials, including 60 cases in areas occupied by Russian forces and those loyal to Moscow.

Zelensky added that "the large number of crimes against the foundations of national security, and the links established between Ukrainian law enforcement officials and the Russian special services" is something that "raises very serious questions," stressing that "every question will be answered."

Venediktova, in particular, led the investigation into alleged atrocities committed at the beginning of the invasion of Russian forces in the city of Bucha, a suburb northwest of Kiev, which in the eyes of the West became a symbol of Russian "war crimes" in Ukraine.

On the ground, six people were killed, Monday, in Russian bombing of the city of Toritsk, located in the Donbass region in eastern Ukraine, according to what the Ukrainian Emergency Service announced on Facebook.

"Rescue workers recovered five bodies. Three people were also removed from the rubble, one of whom died in hospital," a statement said.

And Russia announced on Saturday that it had officially ended a measure it took eight days ago to "stop operations" of its army, and resumed bombing with greater intensity in the Donbass region, which constitutes full control over the main goal of Moscow in the short term.

In the south, the city of Mykolaiv was subjected to "heavy missile attacks on the night of Sunday to Monday," according to what the region's governor, Vitaly Kim, said via Telegram, without mentioning any casualties at the present time.

Putin had warned in early July that Moscow had "not yet started serious matters" in Ukraine.

Russian Defense Minister Sergei Shoigu went to the army command center, where he met officers participating in the attack on Ukraine, according to what the Russian Defense Ministry announced, without giving further details.

The ministry said the minister "gave directions to make destruction a priority, through the use of high-precision weapons, artillery and long-range missiles."

In Russia, Russian journalist Marina Ovsyanikova, who became a well-known face after she stormed a live television broadcast to denounce the war in Ukraine, said on Monday that she was released hours after her arrest in Moscow.

"I'm home," she wrote on Facebook. All is well. I realize now that it is better to leave the house with a passport and a suitcase."

Her lawyer, Dmitry Zakhvatov, said his client had been arrested on suspicion of "defaming" the army while speaking to a Moscow court she had gone to last week in support of dissident Ilya Iashin, imprisoned for criticizing Russia's offensive in Ukraine.

Her brief arrest came just days after Ovsyannikova demonstrated alone near the Kremlin, waving a placard criticizing military intervention in Ukraine and President Vladimir Putin.

On July 24, the war on Ukraine enters its sixth month, and there is still no comprehensive toll on the civilian casualties of the conflict.