Chairman of the Joint Chiefs of Staff Gen. Mark Milley confirmed Thursday that Ukraine has officially launched a major counteroffensive on its 1,500-mile-long front lines in a move to repel Russian forces from its borders.
"At the beginning of this month, on or about the first of September, Ukraine launched an offensive in order to seize operational and strategic initiative. That offensive is ongoing," Milley told reporters from Ramstein Air Base, Germany. "That offensive is in its early stages."
Milley said it was too early to provide an assessment of how Ukraine is progressing, though reporting this week has suggested that Ukrainian forces made some operational advances in the Kharkiv region in the north as well as the Kherson region in the south.
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"Ukrainians have demonstrated superior tactical proficiency and they've demonstrated a superior will to fight," he added.
The general said Ukrainian forces are effectively using arms supplied by the U.S. and allied nations to counter Russian advances – in some cases pushing into Russia's front lines, according to reports Thursday.
Milley, who stood next to Secretary of Defense Lloyd Austin following a meeting with leaders from the Ukraine Defense Contact Group, said the U.S. and allied nations renewed their pledge to support Ukraine in its fight to "live free of Russian occupation and live free of Russian violence."
Austin said Ukraine will continue to need assistance in air and coastal defenses along with other critical capabilities.
"The United States has stepped up to meet those needs," he said, referring to another $675 million arms package approved for Ukraine Thursday.
The package will include howitzers, artillery munitions, Humvees, armored ambulances and anti-tank systems.
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"So far, the Russian strategic objectives have been defeated," Milley said.
The chairman detailed how Russia launched a second offensive in April after it failed to take Kyiv, overthrow the Ukrainian government or push westward across the country.
Milley also claimed that Russia has failed in its second objective as it has yet to take the Donbas or establish dominance over the Dnieper River – only crossing it in the southern Kherson region, where Ukrainian forces have destroyed at least two bridges Russian forces relied on for supplies.
"Their operational gains, in addition to their strategic gains, have been defeated by a very successful defense conducted by Ukraine," Milley said.
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The general reiterated the U.S.’s long-term commitment to Ukraine but warned "the war is not over."
"Russia's a big country. They have very serious ambitions with respect to Ukraine," Milley added. "So sustainment of Ukraine to continue their fight for their survival will be necessary."