As Trump demands a deal to end the Ukraine war in 50 days, Russia's deputy foreign minister says "demands, especially ultimatums, are unacceptable."

MICHAEL KIMMAGE is Professor of History at the Catholic University of America. He is the author of Collisions: The Origins of the War in Ukraine and the New Global Instability.

Russian President Vladimir Putin is reportedly unfettered from fighting the war against Ukraine until his terms for peace are met, despite U.S. President Donald Trump’s recent threats. His demands may even advance as Russian forces advance further into Ukraine.

Trump’s decision to help Ukraine fight an onslaught of Russian attacks reverses a Pentagon decision to withhold defensive weapons.

One of Vladimir Putin's close allies has outlined a set of demands that Russia wants met to end its violent conflict in Ukraine. Moscow's Foreign Minister Sergei Lavrov insists that a resolution to the fighting cannot be reached unless the "root causes of the conflict" are "eliminated.

Donald Trump has said that US weapons are already “being shipped” to Ukraine as Washington ramps up its military support for Kyiv. A number of Kyiv’s European allies will purchase Patriot air defence missile systems from the US to assist Ukraine’s defence.

One of Vladimir Putin's closest allies has outlined a series of demands Russia wants met to bring an end to its brutal war in Ukraine. Moscow's Foreign Minister Sergei Lavrov has insisted that any agreement to halt the violence cannot be reached unless the "root causes of the conflict" are "eliminated".

It remains to be seen just how lasting and severe President Donald Trump’s turn against Vladimir Putin will be. Trump has criticized the Russian president in unprecedented terms in recent days and signaled he’ll send vital weapons to Ukraine.