Secretary Blinken arrived at Kyiv on an unannounced visit Wednesday, hours after Russia launched its first missile attack in a week against the Ukrainian capital.

Mr. Blinken’s trip aimed to assess Ukraine’s three-month-old counteroffensive and signal ongoing American support for Kyiv’s efforts to drive out the Kremlin’s forces after 19 months of war amid concerns among some Western allies over the pace of progress, according to American officials.

The trip to Ukraine is Mr. Blinken’s fourth since the war began, including one very brief excursion over the Polish-Ukrainian border in March 2022, just a month after the Russian invasion. It will mark the first time America’s top diplomat has spent the night at Ukraine’s capital since he visited Kyiv in January 2022, before the invasion.

Mr. Blinken’s decision to stay overnight at Kyiv is intended to send a symbolic signal of American support for Ukraine as the war drags on.

As a measure of the ongoing challenges, on Wednesday the commander of Ukraine’s ground forces, Oleksandr Syrskyi, said on his Telegram channel that the situation along the eastern front remained difficult. “The enemy does not abandon his plans to reach the borders regions,” Mr. Syrskyi wrote. 

He added, “Our main task is to ensure reliable defense, to prevent the loss of our strongholds and positions in the Kupyansk and Lymansk directions, as well as to successfully move forward and reach the designated lines in the Bakhmut direction.”

In the meantime, a Kremlin-installed official in southern Ukraine stated on Tuesday that Russian forces withdrew from the village of Robotyne just more than a week after Kyiv announced its recapture.

“The Russian army abandoned — tactically abandoned this settlement,” the Russian-appointed governor of Ukraine’s occupied Zaporizhzhia region, Yevgeny Balitsky, stated.

At Kyiv on Wednesday, Mr. Blinken laid a wreath at the Berkovetske cemetery to commemorate members of the Ukrainian armed forces who lost their lives defending the country.

He is expected to meet with President Zelensky, Prime Minister Denys Shmyhal, and the foreign minister, Dmytro Kuleba, to discuss the ongoing counteroffensive and reconstruction efforts.

Those Washington officials said possible alternative export routes for Ukrainian grain will also be discussed following Russia’s exit from the Black Sea Grain Initiative and its frequent bombardment of port facilities in the Odessa region from where most grain is transported abroad.

Near Odessa region one person was killed in a Russian missile and drone attack that hit Izmail port. The attack damaged grain elevators, administrative buildings, and agricultural enterprises, local authorities said.

Mr. Blinken’s visit is expected to include the announcement of new military aid of between $175 million to $200 million. Another larger military assistance package is expected later this week.

Other issues, including support for Ukraine’s war-torn economy, will be discussed, building on Mr. Blinken’s June announcement in London of $1.3 billion in aid to help Kyiv rebuild, with a focus on modernizing its energy network that was bombarded by Russia last winter.

The secretary’s visit comes after some of Ukraine’s allies have privately expressed concern that Ukrainian troops may come up short and fail to reach their objectives.

While Washington has been concerned by certain day-to-day battlefield setbacks, Ukraine’s handling of the military situation, particularly its air defense capabilities in knocking down Russian drones aimed at Kyiv, has been impressive.

Mr. Blinken aims to get a view on how the counteroffensive operation is progressing and what kind of support is required in the current phase of the battle, including materials to break through dense Russian defense lines while the winter season looms. Air defense will also continue to be a priority.

On the train journey to Kyiv, Mr. Blinken met with the Danish prime minister, Mette Frederiksen, also on an official visit, to discuss the war. Mr. Blinken thanked her for Denmark’s leadership in a coalition training Ukrainian pilots on F-16s and for promising to donate the fighter jets to Ukraine, according to a Department of State representative.

Overnight, Russia fired cruise missiles at Kyiv in the first aerial attack on the capital since August 30, according to the head of Kyiv’s regional military administration, Serhii Popko.

Debris from a downed missile struck the premises of a business at the capital, igniting a fire and causing damage to the company’s equipment. No casualties were reported.