NATO leaders will gather in Ankara for a summit on Tuesday and Wednesday, amid pressure from President Donald Trump for Europe ‌to step up defense spending and following months of transatlantic friction over the Iran war and Greenland.

The U.S. president's frequent criticism of NATO, along with announced troop withdrawals from Europe and a six-month review of the U.S. military presence on the continent, has fueled uncertainty within the alliance.

Here is what you need to know about the summit:

What will leaders discuss?

The Trump administration has pushed for Europe to boost defense investment and take on primary responsibility for the continent's defense.

Officials expect leaders to focus ‌on progress towards defense spending targets, boosting defense industrial production and how to implement "burden-shifting" from the U.S. to Europe.

Which leaders will be ​there?

Leaders from NATO's 32 member countries, including Trump, will attend the summit.

Ukrainian President Volodymyr Zelenskiy, South Korean President Lee Jae Myung, European Council President Antonio Costa and European Commission President Ursula von der Leyen are expected to join a dinner with ⁠NATO leaders on Tuesday evening.

What will leaders say about defence?

European leaders will aim to show Trump that they are delivering on a pledge ​made at a summit in The Hague last year to spend 5% of gross domestic product on defense and defense-related measures by 2035.

"In 2025, ⁠European Allies and Canada increased their investments in core defense requirements by more than $139bn," leaders are expected to say in a summit declaration, according to a text seen by Reuters.

"We are building the future: a stronger Europe in a stronger NATO - a modernized Alliance. European Allies and Canada, working with the United States, are assuming greater responsibility for the Alliance’s defense," they ‌are set to say.

What will NATO members do for ukraine?

NATO members are expected to reaffirm support for Ukraine and pledge further assistance.

"For ​2026, Allies pledge €70bn ‌in military equipment, assistance and training for Ukraine and affirm their sovereign commitments to sustaining at least equivalent levels in 2027," the leaders are expected to say.

Part of the funding will come from existing bilateral pledges and an ‌EU loan facility that provides €60 billion for Ukrainian defense investment and procurement for 2026-2027. The United States is not expected to contribute funding.

What will the alliance do on industry?

While last year's summit focused on agreeing a new spending pledge, officials want this year's gathering to focus ⁠on scaling up weapons production and boosting defense innovation.

The alliance will ‌host a defense industry forum in Ankara on Tuesday, ⁠where deals worth tens of billions of dollars will be announced.

Will iran come up?

European officials are concerned that the Iran war, and Trump's irritation with European governments over their response to ⁠it, could overshadow the ⁠summit.

In their summit declaration, leaders are expected to say that "allies reiterate that Iran must never have a nuclear weapon and call on Iran to fully respect freedom of navigation in the Strait of Hormuz."

What ‌does host turkey want?

Turkey will seek to highlight its growing defense industry capabilities and repeat its longstanding call for alliance members to lift all restrictions on defense trade within NATO.

President Tayyip Erdogan will also want to make progress with allies such as France and Italy on the purchase of SAMP/T missile defense systems ‌and other defense industry ​cooperation.

In bilateral talks with Trump, Erdogan is ‌expected to highlight improving ties between Ankara and Washington while pressing for the lifting of U.S. sanctions and renewed access to the F-35 fighter jet program.

Who else is coming?

Also in Ankara, NATO foreign ministers are expected to meet counterparts from Bahrain, Kuwait, Qatar and ​the United Arab Emirates, and to hold a dinner discussion with Ukraine's foreign minister and European Union foreign policy chief Kaja Kallas.

NATO defense ministers are also set to hold talks with ministers from Australia, Japan, New Zealand and South Korea.