Russia has suffered between 70,000 and 80,000 casualties, either killed or wounded, since its invasion of Ukraine began, the Pentagon's Under Secretary of Defence for Policy, Colin Kahl, said on Monday.
Meanwhile, the United States will send an additional $5.5 billion in aid to Ukraine, made up of $4.5 billion in budgetary support and $1 billion in military assistance, to help it come to grips with the turmoil of this year's Russian invasion.
The $4.5 billion budgetary grant will fund urgent government needs including payments for pensions, social welfare and healthcare costs, bringing total US fiscal aid for Ukraine to $8.5 billion since Russia's February invasion, the US Agency for International Development said.
The funding, coordinated with the US Treasury Department through the World Bank, will go to the Ukraine government in tranches, beginning with a $3 billion disbursement in August, USAID said.
It follows previous transfers of $1.7 billion in July and $1.3 billion in June, USAID said. Washington has also provided billions of dollars in military and security support.
The $1 billion arms package announced by the Pentagon is the largest single military package under president Joe Biden's drawdown authority, including long-range rocket munitions and armored medical transport vehicles
It includes as many as 50 M113 armored medical transports and munitions for the US-supplied HIMARS long range rocket launchers and for the NASAMS surface-to-air missile system.
The fiscal and military aid packages - both first reported by Reuters on Monday - are drawn from a $40 billion aid package for Ukraine approved by Congress in May.
Overall, the United States has contributed more than $18 billion to Ukraine this year.
The new budgetary funds are to help the Ukrainian government maintain essential functions, including social and financial assistance for the growing poor population, children with disabilities, and millions of internally displaced persons, as the war drags on.
Ukrainian officials estimate the country faces a $5 billion-a-month fiscal shortfall - or 2.5 per cent of pre-war gross domestic product - due to the cost of the war and declining tax revenues. Economists say that will swell Ukraine's annual deficit to 25 per cent of GDP, compared with 3.5 per cent before the conflict.
The World Bank estimates that 55 per cent of Ukrainians will be living in poverty by the end of 2023 as a result of the war and the large numbers of displaced persons, compared with 2.5 per cent before the start of the war.
