To Ukraine next. And America's top diplomat, Secretary of State, Anthony Blinken, has arrived in the country for an unannounced visit. Mr. Blinken came in by sleeper train and was greeted by senior officials. His visit comes as weapons from a new USAID package begin arriving at the front line. Ukrainian forces are struggling to hold back a major Russian incursion near its second biggest city of Kharkiv. Well, let's go live to Kyiv and our correspondent, James Waterhouse. So James, this unannounced announced visit from Mr. Blinken. He, I understand, expected to meet President Zelenskyy.

Yes, Mr. Blinken is going to get the full rota call of Ukraine's top officials. He'll meet with President Zelenskyy later this afternoon, not before having a working lunch with his Ukrainian counterpart, Dimitro Kuleba. As you say, he had the pleasure of the nine-hour sleeper train from Poland. It's the way all officials have to make their way to Ukraine's capital with there being a no-fly zone over the whole of the country in these times of war. You can be sure what will come up will be the gradual arrival of this ammunition and weaponry as part of this $61 billion package, which was unlocked a month ago after a lot of political disagreement in Washington. You can be sure that Mr. Blinken will be told about this continued Russian incursion in the northeast east of Ukraine, which is only gathering momentum for the Russian side. We're told in some areas now, around 35,000 troops have now joined that attack, and they are looking to take more and more Ukrainian territory in that area. Here in this new part of the front line. So the White House, Anthony Blinken is calling this a visit. It's a statement of resilience, they say, and it is a much needed show of support.

America is the biggest military backer of Ukraine by some way. So this is a timely visit, and Ukraine will be pointing to what is going on on this part of the front line as a reason for the West to continue to support Ukraine as it sees it. So a welcome visit. He will have a busy day. It's a two-day trip to the sunny capital of Ukraine, and we wait to see what comes out of it. I imagine the focus will very much be on the speed of the delivery of that Western weaponry.

Yeah, just how important are those US weapons on the front line, particularly around Kharkiv?

Well, we're told by US officials that ammunition has already started to arrive. So that means in the artillery shells and long-range guided missiles or attackums, as they are known. And Ukraine has used them extensively in the past on Russian supply lines, on ammunition depots, on command centers. And you have to look back quite a long way now. Two years ago, when Ukraine was liberating territory last, it used those long-range strikes to isolate Russian troops and make their presence, their occupation unsustainable in some areas. So the distant ambition, I think, for defending troops will be to simply do that again. But I think because of the way things are going in the East and Northeast, where you have building Russian momentum, at the moment, this ammunition can only really be used to just suppress those Russian advances to try and gain some parity, which has long been lost. And that is what generals are being upfront about as well as President Zelenskyy. The goal with this American aid is to simply stay in the fight, to stabilize the front line. So I think there's a bit of expectation management going on in Kyiv in that regard.

James Autohaus in Kyiv. Thank you very much indeed. And you can get more analysis of Anthony Blinken's visit to Ukraine online from our US State Department correspondent, Tom Bateman, who is traveling with the Secretary of State. You will find that at bbc. Com/news or on the BBC News app.