NATO leaders decided Wednesday to formally invite Finland and Sweden to join the alliance after Turkey agreed to withdraw its reservations, according to a statement.

"Today, we have decided to invite Finland and Sweden to become members of NATO, and agreed to sign the Accession Protocols," a statement said.

Finland's President Sauli Niinisto confirmed on Tuesday that Turkey has agreed to support Finland and Sweden's joint membership of NATO, on the first day of the alliance's summit in the Spanish capital Madrid.

Niinisto said the breakthrough came after the three countries signed a joint memorandum "to extend their full support against threats to each other’s security."

NATO Secretary-General Jens Stoltenberg told reporters, "I am pleased to announce that we now have an agreement that paves the way for Finland and Sweden to join NATO."

NATO leaders call Russia "appallingly cruel"

According to NATO leaders on Wednesday, Moscow now presented a "direct danger" to the Western alliance.

Read more: NATO to consider Russia a threat and China a "strategic challenge"

In a declaration from the Madrid summit, the leaders stated that "Russia's appalling cruelty has caused immense human suffering and massive displacements, disproportionately affecting women and children."

Jens Stoltenberg, Alliance leader, unveiled a new combined package of more aid, including secure communications technology and anti-drone devices, saying "Ukraine can count on us for as long as it takes."

The summit decided on a new NATO strategy, stating that Russia "is the most significant and direct threat to Allies’ security and to peace and stability in the Euro-Atlantic area".

The document updated for the first time since 2010 stated that "we cannot discount the possibility of an attack against allies’ sovereignty and territorial integrity."

The summit statement added that "allies have committed to deploy additional robust in-place combat-ready forces on our eastern flank."

NATO: China's "coercive policies challenge our interest"

For the first time in its guiding document, NATO acknowledged on Wednesday that China's power poses a risk to the alliance and that Beijing's deeper connections to Moscow were detrimental to Western interests.

"The People’s Republic of China’s (PRC) stated ambitions and coercive policies challenge our interests, security, and values," the summit concept stated.

"It strives to subvert the rules-based international order, including in the space, cyber and maritime domains."

NATO accused China of targeting NATO members with its "malicious hybrid and cyber operations and its confrontational rhetoric."

Despite some countries' reluctance to shift focus away from Europe, NATO's leading power, the United States, has pushed for the alliance to pay greater attention to China.

Following the war in Ukraine, Russia was identified as the "most significant and direct threat to allies’ security," according to NATO's guiding document, which was revised for the first time since 2010.

It further stated that growing connections between Moscow and Beijing "run counter to our values and interests."

Leaders from Asian partners Japan and South Korea were attending a NATO meeting for the first time, indicating growing concerns about China.