What was significant about the recent diplomatic talks in Saudi Arabia regarding the Ukraine war?

The talks in Riyadh marked a groundbreaking diplomatic event where Russian and American officials held four hours of discussions aimed at ending the war in Ukraine. What made these talks particularly significant was that neither Ukraine nor European nations were invited to participate. Instead, the US sent a separate envoy to meet Ukrainian officials in Kyiv. This arrangement has sparked considerable unease among European leaders, who held an emergency summit in Paris to discuss Ukraine and European security concerns regarding President Trump's plans to resolve the conflict. The exclusion of key stakeholders has raised questions about the future direction of negotiations.