The involvement of US President Donald Trump in a peace agreement for Ukraine "is essential" and any peace must be just and durable, Europe's role being "equally essential," President Nicusor Dan wrote on Tuesday on his Facebook page.The head of state conveyed the message after participating in the online meetings of the Coalition of the Willing and the European Council, convened on Tuesday after Donald Trump's meeting in Washington with Ukraine's President Volodymyr Zelenskyy, who was accompanied by seven European leaders."Today's Coalition of the Willing and the European Council video conferences addressed the results of last evening's important talks in Washington on Ukraine's security," Romania's President showed.He said that the main points which he underscored were transatlantic coordination, an element which "remains the strongest asset" in deterring Russia's aggression, the fact that Russia must stop killing civilians if it is truly committed to achieving peace.Moreover, the head of state showed that sanctions must be kept and, if needed, even intensified until a peace agreement is reached."We must ensure the immediate return of all abducted Ukrainian children - Romania will keep supporting this effort. Romania will contribute to strong security guarantees for Ukraine, to be implemented through close cooperation between Europe and the US - this is an investment in Europe's security, not just in Ukraine's," Nicusor Dan said.He highlighted that "a peaceful Ukraine also strengthens Romania's security and benefits our neighbor, the Republic of Moldova."President Nicusor Dan attended on Tuesday an online meeting of the European Council and the Coalition of the Willing from the Special Operations Forces Command (SOFC) in Targu Mures, a military unit which he also visited today, according to the Presidential Administration.US President Donald Trump met on Monday in Washington with Ukraine's President Volodymyr Zelenskyy. The meeting was followed by a gathering with seven European leaders.As he welcomed his Ukrainian counterpart, Volodymyr Zelenskyy and European leaders, who expressed their willingness to work together for the future peace and security of Ukraine, the US President said that this war will end, according to AFP.