Russia's advance on Kyiv hit more resistance and is moving slower than expected, US defense official says

• Russia invaded Ukraine early Thursday morning and has been attacking its cities, including the capital.
• A US Defense official said Russia is "not moving on Kyiv as fast as they anticipated they would do." Experts have said the same.

Russia appears to have "lost a bit of momentum" as they continue their invasion of Ukraine, a senior US defense official told reporters on Friday.

The official said Russian forces are "not moving on Kyiv as fast as they anticipated they would be able to" and are "meeting more resistance than they expected," CNN reported.

Russia launched a large-scale invasion of Ukraine early Thursday morning, entering the country from several directions, with many of its forces pushing towards the capital city of Kyiv. Russian forces, which have launched various strikes on Kyiv, have also been attacking other cities.

There have been different reports of casualty counts for both the defenders and the invaders, with the numbers varying greatly, but there are indications that the Russians are sustaining losses.

Michael Kofman, a Russia expert at CNA, tweeted Friday that "it looked as though Russian forces were expecting a quicker [Ukraine] military collapse and easier gains."

"So far we've seen only a fraction of the Russian force arrayed for the operation," he continued, adding that it is "unclear if Russian forces reached initial objectives, but best estimate is they expected more rapid gains [and] less resistance."

The UK's Defense Minister Ben Wallace appeared to be of the same view when he spoke with British media, saying that Russia is "behind its hoped for timetable."

"Our assessment, as of this morning, is that Russia has not taken any of its major objectives," Wallace told Sky News, adding that Putin intends "to invade the whole of Ukraine."

The senior US defense official who spoke to reporters Friday said as well that no major population centers have been taken, but the official added that the US believes Russia has committed only about a third of the forces it amassed at positions around Ukraine to the fight, according to two Reuters reporters.

"They have an have continued to have at their disposal significant combat power of a combined arms nature," the official said, according to Defense News' Joe Gould. "They are meeting resistance but they have a lot of power at their disposal."