As NATO countries consider their applications, the U.S. has total, complete backing, according to President Joe Biden.
During a press conference at the White House with Niinisto and Biden, he said that Sweden and Finland meet all NATO requirements and have strong support from the U.S.
The reports will be sent to Congress for the Senate to consider the applications as soon as possible.
Turkey has said it will reject applications from Sweden and other NATO member countries because they support organizations that Turkey considers to be terrorists.
Niinisto said that Finland is committed to Turkey's security and that it is open to discussing all concerns.
Niinisto hopes that the U.S. can set an important example for others by quickly ratifying the alliance.
Turkey doesn't join NATO because of its support of Kurdish groups, according to Turkish President Recep Tayyip Erdogan. Turkey has been fighting against armed Kurdish groups for decades, and has accused Sweden of supplying weapons to the Kurdistan Workers Party, but Sweden denies. Turkey isn't a NATO member, but it wants to reach an agreement, according to the Turkish officials. Turkey has told its NATO allies that it will not accept the membership applications of Sweden and Finland.
NATO Secretary-General Jens Stoltenberg is confident that NATO members will make a quick decision on welcoming Finland and Sweden into the alliance.
After conducting security reviews due to Russia's invasion of Ukraine, Sweden and Finland submitted their applications to join NATO on Wednesday. After 200 years of military nonalignment, Sweden has chosen a new path, according to Andersson. The masks have fallen, and we see only the cold faces of war, as a result of Russia's war in Ukraine. Russia's invasion in 1939 started a year-long war that ended with Russia ceding most of its territory to it. Russia warned that it would have to balance the situation with military and political consequences if it joined NATO.
The historic moment is that Finland and Sweden apply to join NATO.
In his most definitive statement yet, Turkey's Erdogan told Allies it would say no to the NATO bids.