KYIV, Ukraine (AP) Ukrainian forces withdrew from some areas of the countrys east and battled Russian troops in others on Wednesday, as President Volodymyr Zelenskyy postponed all his upcoming foreign trips, underscoring the seriousness of the threat his soldiers are facing.

Against that grim backdrop, U.S. Secretary of State Antony Blinken sought to reassure the ally of continuing American support, announcing a $2 billion arms deal most of the money coming from a package approved last month.

The top diplomat is in Ukraine as Russian troops press a fresh offensive in northeast Ukraines Kharkiv region. It began last week, marking the most significant border incursion since the full-scale invasion began and forcing almost 8,000 local people to flee their homes. Together with Moscows weekslong effort to build on its recent gains in the eastern Donetsk region, the more than two-year war has entered a critical stage for Ukraines depleted army.

Ukraines General Staff reported late Tuesday that troops fell back from areas in Lukyantsi and Vovchansk in order to save the lives of our servicemen and avoid losses.

Vovchansk just 5 kilometers (3 miles) from the Russian border and 50 kilometers (30 miles from the city of Kharkiv has been the focus of much of the recent fighting, and Ukrainian and Russian troops battled in its streets on Wednesday. Oleksii Kharkivskyi, head of the citys patrol police, said Russian troops were taking up positions in the city, while the Ukrainian General Staff said its forces were trying to flush them out.