In their letter, representatives of the left wing of Biden's Democratic Party condemned the "egregious and illegal invasion of Ukraine" by Russia. They also agreed with the White House that a peace settlement would depend on Ukraine's agreement.

However, the group, led by MP Pramila Jayapa, stressed that the multi-billion dollar US military aid to Ukraine carries with it a responsibility to "seriously explore all avenues" to end the conflict. As possible elements of a negotiated solution, the parliamentarians named "incentives to end hostilities" - such as the easing of sanctions - and security guarantees from the international community for a "free and independent Ukraine".

The spokesman for the State Department in Washington, Ned Price, said that the US government had not seen any indication from the Russian side that they were willing to engage in "diplomacy and dialogue". The US provided military aid to Ukraine with the aim of putting it in "the strongest possible position" for possible negotiations with Russia.

In May, the US Congress launched a $40 billion (€40.5 billion) aid package for Ukraine, which will finance extensive military aid. The US is supplying the Ukrainian army with rocket launchers, drones, artillery ammunition and vehicles, among other things.