Transition from Biden to Trump makes for a unsettling period for Ukraine

The type of mines being supplied indicates the type of battle now being fought.

It's an infantry war. Russia is deploying waves of soldiers, regardless of casualty rates: men on the battlefield, boots literally on the ground in large numbers, including now 10,000 North Korean soldiers.

That's a reflection both of the human loss Putin is willing to allow but also the desperate nature of the fight right now.

The long frontline in the east of Ukraine has inched westward as Russia has made incremental gains with a seemingly endless supply of manpower (helped by North Korea).

Anti-personnel landmines are the controversial solution to slow that advance. Bluntly, they can kill and injure large numbers of troops on the battlefield.

Arms control groups are dismayed by the announcement, given the legacy of risk to civilians. But the US Defence Department insists that the type of mines they are providing are "smarter" than the self-made mines the Ukrainians are using now.

They are "non-persistent", becoming inert after a pre-set period of time (anywhere from four hours to two weeks). They are electrically fused and require battery power to detonate. Once the battery runs out, officials say, they will not detonate.

The decision to send the mines is indicative of a broader strategic objective too.

In less than two months, President Biden will step down. On 20 January, Donald Trump will become president.

He has pledged to bring the war to an end "in a day". He has not said how he will achieve this. Would it involve ceding Ukrainian land to Russia? Almost certainly.

And so, it is logical that over the next two months both sides will want to make as many territorial gains as they can before the frontline is frozen. In the case of Ukraine, it may now simply be about holding the line - in part with the American mines.

Look at a map too. The further west the eventual settlement line sits, the longer the border will be, north to south. And the longer, or wider the border is, the more challenging it is for Ukraine to defend and fortify in the years ahead. Ukraine needs to hold the line.

'Lower nuclear threshold is a thinly veiled warning'

The bloodiest part of a war is usually in the weeks before a treaty is signed to end the fighting. There is every reason to think this will be the case in this war.

There is only ever one American president at a time. But right now it does feel a little like there are two presidencies in parallel. Biden outgoing; Trump incoming.

Ukraine is trying to appeal to both. I was struck this week by the language the Ukrainian foreign minister used at the United Nations in New York.

He used the phrase "peace through strength" and he emphasised it. It is precisely the same phrase Donald Trump has used consistently through his campaign.

Trump's vision to "Make America Great Again" is the concept of "peace through strength".

Ukraine is, essentially, now saying to Donald Trump - "we agree with you… our peace, Europe's peace, the West's peace is achieved through strength - Ukraine's strength to push Russia back. Help us".

Ukraine is very intentionally parroting Donald Trump. They are banking too on the fact that Trump doesn't like to lose or be seen as weak - against Putin.

The problem is that Trump also likes short term wins. He doesn't necessarily see the longer term strategic implications.

A short term gain here would be to bring an end to the conflict - a frozen frontline, Ukrainian land handed to Russia. Trump would be self-cast as the peacemaker.

Longer term, would Russia simply regroup to fight another day, to push further west in several years time? And what message would a capitulation to Russia send to other world leaders with expansionist territorial ambitions?

These two months, between presidents, present unsettling times - positioning and jockeying by all sides, preparing for a new, very different White House.

-SKY NEWS