Türkiye has been in talk with Finland and Sweden to address the concerns, which include the PKK terror group's activities in both countries.
The US recognises Türkiye's legitimate concerns over Finland and Sweden's NATO membership bids and is hopeful for a "positive resolution" soon, a senior State Department official said.
Speaking at a Senate Foreign Relations Committee hearing that discussed the proposed accession of the two Nordic nations to NATO, Karen Donfried, the assistant secretary of state for European and Eurasian affairs, said their participation would bolster the NATO alliance.
"Both countries will enhance NATO's situational awareness and capabilities in the high north," she said, adding they would also enhance the national security interests of the US.
In her remarks, Donfried recalled that Ankara raised concerns about some of Finland and Sweden's policies in advance of their accession.
"We recognise Türkiye's legitimate concerns regarding terrorism, which NATO Secretary-General Stoltenberg has also highlighted," she said.
Türkiye, Finland and Sweden are currently in talks to address the concerns, which include the YPG/PKK terror group's activities in both countries.
"The decision within NATO is a consensus decision. And Türkiye has raised some concerns relating to terrorism and the approach of Sweden and Finland. Of course, the United States along with Türkiye shares the desire to end the support of terrorism, and we all take this very seriously," Donfried underscored.
The last talks took place on Monday, which she called "constructive.”
"So we are confident that there will be progress here. And that will allow the accession protocols to be signed and the ratification process here to move forward," she added.
Sweden and Finland, amid their NATO bids, are under pressure from Türkiye to end their support for the PKK/YPG terror group, with Ankara saying that NATO is a security alliance and that any potential members must take a clear stance against terrorism.