US President Donald Trump’s 50-day pause ahead of possible secondary sanctions on Russia gifts the Kremlin a window to exploit the incremental gains of recent weeks in Ukraine’s east.

On Monday, Trump said that Russia's failure to reach a negotiated settlement with Ukraine within 50 days would lead to his administration imposing a 100% tariff rate on Russian imports as well as what he called "secondary tariffs" on countries that have continued to do business with Moscow.