What are the key concerns surrounding the US-Russia talks on Ukraine?

The US-Russia talks in Saudi Arabia have sparked significant concern in Ukraine and Europe due to the US's recent outreach to the Kremlin. While both sides have downplayed expectations of a breakthrough, European leaders held an emergency meeting in Paris to assert their position that they must have input in any Ukraine negotiations. Leaders from Germany, UK, Italy, Poland, Spain, Netherlands, Denmark, NATO and the European Union strongly pushed back against the idea that the US and Russia could negotiate an end to the Ukraine war without European participation. This highlights the tension between bilateral US-Russia diplomacy and Europe's desire for multilateral involvement in resolving the conflict.