During a meeting of the Russian Security Council, Russian President Vladimir Putin said that Western countries seem to be determined to fight until the last Ukrainian, Sputnik reported. 

"[Military] equipment, of course, can be supplied additionally. But the mobilization reserve is not unlimited. And it seems that Ukraine's Western allies really decided to fight Russia to the last Ukrainian," Putin pointed out.

Read more: After $6.3bln accounting 'error', US announces $1.3bln aid to Kiev

Earlier today, AFP that Ben Wallace, British Secretary of Defense, announced he was opting out of running for the next NATO chief because of divisiveness among allies. 

"It's not going to happen," The Economist quoted Wallace as saying. 

After playing a primary role in providing weapons for Ukraine during the war with Russia, the UK has been aspiring for NATO leadership by getting it secretary of defense to be elected as the alliance's chief. 

Ukrainian President Volodymyr Zelensky has been desperate for fighter jets, repeatedly pushing for advanced Western jets, but Kiev's international supporters had balked at doing so until recently.

Several NATO allies have offered to train Ukrainian pilots in flying F-16s. US President Joe Biden told G7 leaders that Washington will endorse supplying advanced warplanes including F-16s to Ukraine and will support efforts to train Kiev's pilots, a senior White House official revealed.

Biden said the United States "will support a joint effort with our allies and partners to train Ukrainian pilots on fourth-generation fighter aircraft, including F-16s, to further strengthen and improve the capabilities of the Ukrainian Air Force," according to the official.

Read more: Ukrainian Air Force pilots plead for F-16s, say Su-25s useless: CNN