Will NATO disappoint Ukraine again in Washington?

When NATO leaders welcome Ukrainian President Volodymyr Zelensky to their summit in Washington this week, they will reaffirm that Kyiv will one day become a member and vow to keep arming its troops.

But they will not give Zelensky what he wants most: a firm invite for his war-torn country to join their nuclear-armed alliance anytime soon.

Last year, NATO's failure to issue Ukraine a clear timeframe for membership did not go down well.

Zelensky unleashed a diplomatic firestorm at NATO's 2023 summit in Lithuania by blasting the alliance's refusal as "absurd".

Still, in the end he did not get leaders to budge from saying that an invite would only come "when allies agree and conditions are met".

In Washington, Western officials say they are hoping to avoid another bust-up -- with Zelensky being told clearly there will not be concrete progress.

Multiple diplomats said that NATO chief Jens Stoltenberg set out what was on offer at a meeting with the Ukrainian leader ahead of time.

"The scene is better prepared now," said one NATO diplomat, speaking like others under condition of anonymity.

"Zelensky will have to accept whatever is offered."

A smooth summit is particularly important for US President Joe Biden as he struggles to right his reelection campaign after a damaging debate performance.

- 'Close to zero' -

Two and a half years into Russia's full-scale war, Ukraine remains adamant that getting under the protective umbrella of the US-led alliance is its only long-term guarantee for security.

But in Kyiv there is an acceptance that the Washington summit will not bring the country any closer towards NATO membership.

"The chances of getting an invitation are close to zero," a high-ranking Ukrainian official said.

The official added, however, that Kyiv hoped to parlay the "sense of guilt" among allies over the lack of progress into advances in other areas.

Most reluctant on bringing Ukraine closer to the fold are heavyweight powers the United States and Germany -- long cautious of dragging NATO closer to a war with President Vladimir Putin's Russia.

Diplomats say that Kyiv has made some progress on key reforms such as in military procurement, but there is still much work to do rooting out graft.

In a push to offer Ukraine encouragement, NATO diplomats say they are debating calling Kyiv's membership push "irreversible" in the summit declaration.

The alliance will also likely speak about setting Kyiv on a "bridge" towards joining, officials say.

"Putin has said Ukraine should not be in NATO, so Washington should give a very strong response indicating that it is an irreversible process," said a European diplomat

Beyond tweaks in wording, NATO says it will also put Western support for Kyiv on a firmer footing.

Part of that will be done by having the alliance take over coordination of weapons deliveries from the United States.

Diplomats say that should help insulate supplies should former US president Donald Trump return to the Oval Office.

NATO allies have also hashed out a pledge to keep on providing support to Kyiv at roughly the rate -- 40 billion euros ($43 billion) a year -- that they have been since Russia invaded.

But the promise is not legally binding -- and Washington watered it down further by insisting it needs to be reviewed next year.

- More Patriots? -

The most important -- and concrete -- help Zelensky appears likely to get in Washington is commitments of new air defence systems to better defend Ukraine's skies.

Kyiv said back in April that it desperately needed seven more Patriot missile systems to help intercept Russia's devastating attacks.

Since then only three advanced air defense systems have been offered -- by Germany, Romania and Italy.

Reportedly, the United States is now mulling over announcing a further Patriot system for Kyiv, while a Dutch-led initiative to assemble another could yield results.

"I think we'll have some additional good news for them on that front," a senior US official said.

Ahead of the summit, US Defense Secretary Lloyd Austin said Washington will provide a new $2.3 billion package including key air defense.

One diplomat said that while the rest of the summit might "lack meat", getting more air defenses could at least leave Zelensky feeling like he had scored a win.

"What would you want more? Nice words in a declaration that don't mean much or military support?" the diplomat asked.

"If you're the Ukrainian president you obviously want the military support."