Why Zelenskyy cannot adhere to one of Trump's demands on how he can end war 'almost immediately'

There's a reason why President Zelenskyy cannot follow through with Donald Trump's demands that could end the war 'immediately'.

Ukraine have been embroiled in bloodshed with Russia since February 2022, after Vladimir Putin sent troops into the neighboring country in the hopes of taking over. Over three years later and Russian the army only occupies around 20 percent of Ukraine (which is approximately 28 times smaller than Russia).

Since being sworn in as president for second time in January, Trump has made it his mission to bring Ukraine and Russia's war to an end.

He had a disastrous meeting with Zelenskyy at the White House earlier this year and more seemingly more successful meeting with Putin in Alaska last week.

A peace deal is still to be reached, however, but this may all change after Zelenksyy sits down with Trump today (August 18) in Washington.

What has Trump said Ukraine needs to do?

Putin and Trump met in Alaska on August 15 (Andrew Harnik/Getty Images)

Ahead of his meeting with the Ukrainian president, Trump outlined to the two things the country needs to do that could end the conflict 'almost immediately'.

Taking to Truth Social, the POTUS penned: "President Zelenskyy of Ukraine can end the war with Russia almost immediately, if he wants to, or he can continue to fight.

"Remember how it started. No getting back Obama given Crimea (12 years ago, without a shot being fired!), and NO GOING INTO NATO BY UKRAINE. Some things never change!!!"

How has Zelenskyy responded?

Zelenskyy is now in Washington to meet with Trump (Ben Stansall - WPA Pool/Getty Images)

Shortly after Trump's post, Zelenskyy shared a statement of his own to Twitter.

"I have already arrived in Washington, tomorrow I am meeting with President Trump," his tweet began. "Tomorrow we are also speaking with European leaders. I am grateful to @POTUS for the invitation."

Zelenskyy went on: "We all share a strong desire to end this war quickly and reliably. And peace must be lasting. Not like it was years ago, when Ukraine was forced to give up Crimea and part of our East—part of Donbas—and Putin simply used it as a springboard for a new attack.

"Or when Ukraine was given so-called 'security guarantees' in 1994, but they didn't work. Of course, Crimea should not have been given up then, just as Ukrainians did not give up Kyiv, Odesa, or Kharkiv after 2022."

"I am confident that we will defend Ukraine, effectively guarantee security, and that our people will always be grateful to President Trump, everyone in America, and every partner and ally for their support and invaluable assistance," Zelenskyy further penned.

"Russia must end this war, which it itself started. And I hope that our joint strength with America, with our European friends, will force Russia into a real peace. Thank you!"

Why can't Zelenskyy simply give Crimea to Russia?

Putin wants Crimea to be declared as Russian territory (Andrew Harnik/Getty Images)

While it's clear that the Ukrainian president doesn't want to give Crimea to Russia, he wouldn't be able to do so even if he wanted to.

Under the Ukrainian constitution, a president cannot just change the country's borders. It would have to have a national referendum, which must be authorised by the Ukrainian parliament.

BBC explains that Article 2 of the constitution states that Ukraine's sovereignty 'extends throughout its entire territory', which 'within its present border is indivisible and inviolable'.

Constitution can be changed but not while a country is under martial law, which Zelenskyy declared on February 24, 2022. This is the temporary imposition of military rule over a civilian population, which is usually used during a national emergency.

It's unlikely Zelenskyy will end martial law until a peace deal is finally agreed on.