KYIV (AFP) — Ukraine on Wednesday pressed its surprise offensive in Russian territory and bombarded the neighboring border region of Belgorod, where the governor has declared a state of emergency.

Ukrainian forces entered Kursk region last Tuesday and have taken dozens of settlements in the biggest attack by a foreign army on Russian soil since World War II.

President Volodymyr Zelensky on Tuesday evening posted footage of a video call with his military chief Oleksandr Syrsky, who said that “as of today, our troops have advanced in some areas by one to three kilometers.”

Over the last day, Syrsky added, “control over 40 square kilometers of territory has been taken” and “74 settlements are under our control.”

The head of neighboring Belgorod declared a state of emergency on Wednesday, saying the situation was “extremely difficult” in the Russian border region under Ukrainian bombardment.

“The situation in our Belgorod region remains extremely difficult and tense due to shellings from the Ukrainian Armed Forces. Houses are destroyed, civilians died and were injured,” governor Vyacheslav Gladkov said on Telegram.

Belgorod, which borders Ukraine’s Kharkiv region, had also come under drone attack, he said.

After a week of the Ukrainian advance, Syrsky said Monday that his troops controlled about 1,000 square kilometers of Russian territory.

Kursk regional governor Alexei Smirnov said Monday that 28 settlements had been captured and Ukrainian forces had penetrated at least 12 kilometers deep.

An Agence France-Presse analysis of data provided by the Institute for the Study of War indicated that Ukrainian troops had advanced over an area of at least 800 square kilometers of Russian territory as of Monday.

United States President Joe Biden on Tuesday said the incursion was giving Russia’s President Vladimir Putin a “real dilemma,” in the US leader’s first comments on Kyiv’s surprise attack.

Russia’s defense ministry said Tuesday its troops “continue to repel” Ukrainian assaults and had “foiled” attacks by “mobile groups in armored vehicles.”

Ukraine said it would not hold on to Russian territory it had captured and offered to stop raids if Moscow agreed a “just peace.”

Foreign ministry spokesperson Georgiy Tykhy said Kyiv was not interested in “taking over” Russian territory and defended Ukraine’s actions as “absolutely legitimate.”

“The sooner Russia agrees to restore a just peace... the sooner the raids by the Ukrainian defense forces into Russia will stop,” he told reporters.