Russia is moving reserve forces from across the country and assembling them near Ukraine for future offensive operations, British military intelligence said on Saturday.
A large proportion of the new Russian infantry units are probably deploying with MT-LB armoured vehicles taken from long-term storage as their primary transport, Britain’s Ministry of Defence tweeted in a regular bulletin.
The bulletin comes as Ukrainian defenders battled on Saturday to contain Russian forces along several fronts, officials said.
A missile strike on the northeastern city of Kharkiv wounded three civilians, its governor said, adding that fighters had repulsed two Russian attacks near Dementiivka, a town situated between the city and the border with Russia.
Russia’s Defence Ministry said its forces hit two “bases of foreign mercenaries deployed near Kharkiv.”
Southeast of Kharkiv, attacks continued in Luhansk and Donetsk. Those two provinces, parts of which were held by pro-Russian separatists before the conflict began in February, comprise the eastern industrial region of the Donbas.
Luhansk Gov. Serhiy Gaidai said on the Telegram messaging app that Russian forces were “firing along the entire front line,” though a subsequent Ukrainian counter-attack that hit weapons and ammunition stores had forced Moscow to halt its offensive.
Donetsk regional governor Pavlo Kyrylenko said on the Telegram service that a Russian missile had struck Druzhkivka, a town behind the front line, and reported shelling of other population centres.
Russia, which claimed control over all of Luhansk province last weekend, denies targeting civilians.
Since Russia, which has also seized a big chunk of territory across Ukraine’s south, started what it calls a “special operation” to demilitarize Ukraine on Feb. 24, cities have been bombed to rubble, thousands have been killed and millions displaced.
Ukraine and its Western allies say Russia is engaged in an unprovoked land grab.
Zelensky sacks multiple ambassadors
Meanwhile, Ukrainian President Volodymyr Zelensky dismissed several of Kyiv’s senior envoys abroad.
In a decree posted on the presidential website, Zelensky gave no reason for firing ambassadors to Germany, India, the Czech Republic, Norway and Hungary.
Zelensky has urged his diplomats to drum up international support and high-end weapons to slow Russia’s advance.
U.S. President Joe Biden signed a weapons package for Ukraine on Friday worth up to $400 million US, including four additional high mobility artillery rocket systems (HIMARS).
Zelensky said those armaments were priority needs.
In reaction, the Russian Embassy in Washington said the United States wanted to “prolong the conflict at all costs.”
China-U.S. frictions at G20
On Saturday, U.S. Secretary of State Antony Blinken, urging the international community to join forces to condemn Russian aggression, told journalists he had raised concerns with his Chinese counterpart, Wang Yi, over Beijing’s alignment with Moscow.
The pair held over five hours of talks on the sidelines of the G20 gathering of foreign ministers on the Indonesian island of Bali. On Friday, Russian Foreign Minister Sergei Lavrov had walked out of a meeting there, denouncing the West for “frenzied criticism.”

The Chinese Foreign Affairs Ministry said, without giving details, that Wang and Blinken had discussed “the Ukraine issue.”
It also quoted Wang as saying that Sino-American relations were in danger of being further led “astray,” with many people believing that “the United States is suffering from an increasingly serious bout of ‘Chinaphobia.'”
Shortly before the Russian invasion, Beijing and Moscow announced a “no limits” partnership, although U.S. officials have said they have not seen China evade U.S.-led sanctions on Russia or provide it with military equipment.