五角大楼已经提供了每日更新俄罗斯入侵乌克兰以及乌克兰的努力抵抗。

以下是一名美国高级国防官员周三在第28天对记者说的一些要点:

kacper PEM pel/路透社

艾瑟尔，33岁，来自乌克兰赫尔松，在俄罗斯入侵乌克兰之际，拥抱她的丈夫...

俄罗斯军队在基辅以东面临重大挫折，正在进入防御位置

据一名高级国防官员称，乌克兰军队已经将基辅以东的俄罗斯军队击退到距离市中心55公里的地方，这是一次重大行动。

几个星期以来，就在星期二，俄罗斯军队被阻挡在距离首都中心大约20到30公里的地方。

这名官员说，包法利附近的乌克兰部队“已经能够将俄罗斯人赶回基辅以东和东北约55公里处。”

这位官员周二表示，有迹象表明，在一些地区，乌克兰军队正试图夺回被俄罗斯占领的领土，他们有能力将俄罗斯军队击退近两倍于数周前的距离。这名官员周三表示，“乌克兰人不仅在其中一些地方进行了充分的防御，他们还在其中一些地方发起进攻，实际上将俄罗斯人逼退，或者在基辅的情况下，他们基本上是在迫使他们进入防御状态。”。

该官员称，美国现在评估认为，驻扎在该市以北12至15公里处的俄罗斯军队正在“挖壕沟”并建立防御阵地。这位官员周三告诉记者，“他们正迫使他们进入防御状态”。“所以，这并不是说他们没有前进，实际上他们现在没有试图前进，”这位官员说。"他们采取了更多的防御姿态。"

“我们开始看到他在基辅周围挖壕沟，但真的试图在乌克兰东部发动比以往更多的进攻，投入更多的精力，”这位官员说。

乌克兰人在切尔尼夫击退俄罗斯军队

与此同时，基辅东北部城市切尔尼戈夫的乌克兰军队也成功击退了包围该市数周的俄罗斯军队。这名官员称，那里的乌克兰军队继续“非常努力地”与俄罗斯军队作战，以阻止他们进入该市，在某些情况下，俄罗斯军队已经“放弃了阵地”。“他们实际上正在向相反的方向移动，但移动幅度不大，”这名官员在谈到城市周围的俄罗斯军队时说。

俄罗斯军队现在优先考虑在乌克兰东部顿巴斯地区的行动

这名官员表示，俄罗斯似乎正在“开始优先考虑”他们在乌克兰东部顿巴斯地区(尤其是卢甘斯克周围)的行动，以切断过去八年来一直在那里与俄罗斯分裂分子作战的乌克兰军队。“我们仍然认为，俄罗斯试图从根本上切断它，从而牵制住在顿涅茨克卢甘斯克地区的乌克兰军队，”这名官员说。

“我们现在看到的迹象表明，俄罗斯人真的开始优先考虑乌克兰东部的那部分，”这名官员说。“我们相信他们现在将开始应用，实际上，他们已经在卢甘斯克、顿涅茨克地区，特别是卢甘斯克周围应用了更多的能量。你会看到他们真的在乌克兰的那个地区投入了更多的精力和努力。”

该官员此前曾表示，俄罗斯军队似乎正在努力接管南部港口城市马里乌波尔，这样他们就可以向北推进到顿巴斯，切断乌克兰军队。与此同时，该官员称，该城市的战斗仍然“非常激烈”，他还称俄罗斯和乌克兰军队之间的战斗是“激烈的”。这位官员指出，俄罗斯军队继续用大炮和远程导弹猛烈轰炸这座城市。

与此同时，最近俄罗斯在西部港口城市敖德萨周围的军事活动似乎导致了对该市攻击的猜测，这可能是一个旨在“牵制乌克兰军队”的佯攻。“他们是否真的会对敖德萨采取行动，还不完全清楚，”这位官员说。“所以我们只是我们只是在观察它，看看它会走向何方。”

更多的美国军队前往东欧?

这名官员说，国防部长劳埃德·奥斯汀一直在评估美国在东欧的军事存在，并没有“排除”他将从美国增派部队或从欧洲其他地方重新部署的可能性

但这位官员说，目前没有消息要宣布。他还说，不清楚美国在东欧的军事态势未来会是什么样子。“当然，欧洲的安全环境现在不同了。无论这场战争的结果如何，都将是不同的。

这位官员说:“我认为可以肯定地说，美国和其他北约国家将认真审视我们的足迹是否正确，以及我们的姿态是否适合由此产生的新的安全环境。”。

俄罗斯还有很多导弹可以使用

据这位官员称，俄罗斯现在已经向乌克兰发射了1200多枚导弹，但“我们仍然认为，他们拥有绝大多数组装好的地对空导弹和巡航导弹。”尽管俄罗斯军方已经消耗了大量准备在乌克兰作战的导弹库存，但这位官员指出，“他们仍然有很多剩余。”

这位官员说，俄罗斯军方“在我们的空中发射巡航导弹上运行最低”，但他们仍然拥有“入侵前组装的50%以上”。但是他们仍然拥有大量的地面发射巡航导弹、短程弹道导弹和中程弹道导弹。

Ukraine’s military forces Russian troops east of Kyiv back 55 km from city center

The Pentagon has been providing daily updates on theRussian invasion of Ukraineand Ukraine's efforts to resist.

Here are highlights of what a senior U.S. defense official told reporters Wednesday on Day 28:

Russian troops face major setback east of Kyiv and moving into defensive positions

In a significant movement, Ukraine's military forces have pushed back Russian forces east of Kyiv to 55 kilometers from the city center, according to a senior defense official.

For weeks, and as recently as Tuesday, Russian forces have been kept at bay approximately 20 to 30 kilometers from the center of the capital city.

The official said that Ukrainian forces near Bovary "have been able to push the Russians back to about 55 kilometers east and northeast of Kyiv."

The ability to push back Russian forces nearly twice as far as where they had been for weeks is in line with what the official had said on Tuesday were indications that in some areas Ukrainian forces were attempting to retake territory taken by Russia. "Ukrainians are not only in some of these places up sufficiently defending they're going on the offense in some of these places and actually pushing the Russians backwards, or in the case of Kiev, they're, they're basically forcing them into a defensive position," the official said Wednesday.

The U.S. now assesses that Russian troops that have been stalled 12 to 15 kilometers north of the city are "digging in" and establishing defensive positions according to the official. "They're forcing them into a defensive position" the official told reporters on Wednesday. "So it's not that they're not advancing, they're actually not trying to advance right now," said the official. "They're taking more defensive positions."

"We're starting to see him sort of dig in around Kyiv but really trying to go more on the offense than they have been, more energy applied, in that eastern part of Ukraine" said the official.

Ukrainians pushing back Russian troops in Cherniviv

Meanwhile, Ukrainian troops in the city of Chernihiv, northeast of Kyiv, have also succeeded in slightly pushing back some of the Russian forces that have surrounded the city for weeks. The official described Ukrainians forces there as continuing to fight "very hard" against Russian forces to keep them out of the city and in some cases Russian troops have been "ceding ground." "They are actually moving in the opposite direction, but not by much," the official said of Russian forces around the city.

Russian troops now prioritizing operations in eastern Ukraine's Donbass region

The official said Russia appears to be "starting to prioritize" their operations in the Donbass region of eastern Ukraine, particularly around Luhansk, to cut off Ukraine's military that has been fighting there against Russian separatists for the past eight years. "We still believe that the Russians are trying to basically cut it off and therefore pin down Ukrainian forces that are that are in the Luhansk, Donetsk area," said the official.

"What we're seeing now is indications that the Russians are really starting to prioritize that part of eastern Ukraine," said the official. "We believe that they are now going to start to apply, actually, they have applied a lot more energy in the Luhansk, Donetsk area, particularly around Luhansk. You're seeing them really put more energy and effort into that part of Ukraine."

The official has previously said that it appears that the Russian forces fighting to take over the southern port city of Mariupol so they can then push north into the Donbass to cut off the Ukrainian military. Meanwhile, the fighting in that city remains "very very contested" according to the official who also described the fighting there between Russian and Ukrainian troops as being "hardcore." The official noted that Russian forces continue to heavily bombard the city with artillery and long range missile fire.

Meanwhile, it appears that recent Russian military activity around the western port city of Odessa that led to speculation of an attack on the city may have been a feint intended to "pin down Ukrainian forces." "It's not entirely it's not entirely obvious that they actually will make a move on Odessa," said the official. "So we're just we're just kind of watching that to see to see where it goes."

More US troops going forward to eastern Europe?

The official said that Defense Secretary Lloyd Austin is always assessing the U.S. military presence in eastern Europe and has not "taken off the table" the possibility "that he will flow more forces in from the United States or reposition from elsewhere in Europe."

But for now there are no announcements to make said the official who added that it's unclear what the U.S. military posture in eastern Europe will look like going forward. "Certainly, the security environment in Europe is different now. And it will be different that it will be different no matter what the outcome is of this war," said the official.

"I think it's safe to say that the United States as well as other NATO nations will be taken a hard look at what it whether we have the footprint right and whether the posture is appropriate to the new security environment that results from all this," the official said.

Russia has lots of missiles left to use

According to the official, Russia has now launched more than 1,200 missiles into Ukraine, but "we still assess that they have the vast majority of their of their assembled available inventory of surface to air missiles and cruise missiles available to them." Though the Russian military has expended a lot of the missile inventory readied for operations in Ukraine the official noted that "they still have an awful lot left."

The official said that Russia's military is "running the lowest on our air launched cruise missiles" but that they still have "over 50% of what they had assembled prior to the invasion. But they still have a significant number of ground launched cruise missiles, short range ballistic missiles, and medium range ballistic missiles.