"We are already working on a specific text," Zelensky said in his nightly video address. "Our goal is to make this agreement the strongest of all."

"We are discussing the specific foundations of our security and cooperation. We are also working on fixing specific levels of support for this year and the next 10 years."

He indicated it will likely include agreements on long-term support centering on military hardware and joint arms production, as well as continuing reconstruction aid. "The agreement should be truly exemplary and reflect the strength of American leadership," Zelensky added.

But ultimately a key purpose in locking such a long-term deal in would be to keep it immune from potential interference by a future Trump administration.

Below is what The Wall Street Journal spelled out last year:

The goal is to make sure Ukraine will be strong enough in the future to deter Russia from attacking it again. More immediately, Ukraine's Western allies hope to discourage the Kremlin from thinking it can wait out the Biden administration for a potentially more sympathetic successor in the White House. 

Western officials are looking for ways to lock in pledges of support and limit future governments' abilities to backtrack, amid fears in European capitals that Donald Trump, if he recaptures the White House, would seek to scale back aid. Trump has a wide lead in early polling in the Republican presidential primary field, but soundly lost the 2020 election to President Biden and has been indicted in four criminal cases in state and federal courts.