Kyiv, Ukraine - Ukraine on Wednesday said it had pulled back troops near several villages in the northeastern Kharkiv region, where Russian forces have been advancing and pounding settlements in a new offensive along the border.

President Volodymyr Zelensky canceled planned trips abroad over the fresh offensive and the military was sending more troops to Kharkiv to hold back Russian advances, Kyiv said.

Details of the withdrawal emerged while US Secretary of State Antony Blinken was on an unannounced visit to Kyiv, where Zelensky urged him to speed up US supplies of weapons.

Congress last month finally approved a $61-billion financial aid package for Ukraine following months of political wrangling, unlocking much-needed arms for the country's outgunned troops.

Ukraine conflict Top Ukrainian official reveals China's "unshakeable" stance on issue of territory amid Russian invasion

Moscow launched a surprise major ground assault on the Kharkiv region last week as it seeks to advance across the battlefield, with Kyiv struggling for arms and manpower.

"In certain spots in Lukyantsi and Vovchansk areas, due to the fire impact and assault actions of the enemy, maneuvers were carried out in order to save the lives of our soldiers, units were removed to advantageous positions," a military spokesman said on state television.

Authorities in Vovchansk said there was intense street-to-street fighting in the border town that before the war had an estimated population of 20,000 people.

"We are here and are evacuating people and helping them. The situation in Vovchansk is extremely difficult," police chief Oleksiy Kharkivsky said on social media.

The interior ministry announced that three civilians had been killed in the Kharkiv region over the last 24 hours and that a Russian drone had wounded two police officers.

Throughout the two-year war, both sides have typically used the language of moving to more "advantageous positions" to signify retreats.

The two villages – around 18 miles apart – are close to the border with Russia and have been targeted in the fresh offensive.

Joke of the Day Joke of the Day for July 26, 2024: The best jokes to get your funny on

The Ukrainian military said the situation "remains difficult" but insisted that its forces were "not allowing the Russian occupiers to gain a foothold".

Zelensky's spokesman said on social media that the president had postponed upcoming trips, including one to Spain, and reiterated that the military was rushing reinforcements to the area to prevent Russia from punching through.

"Additional forces are being deployed, and there are reserves," Zelensky's office said.