Trump says Russia and Ukraine to "immediately" start ceasefire talks

After reviewing the provided list of articles, I have compiled a summary of the key points as follows: US President Donald Trump has announced his intention to speak with Russian President Vladimir Putin on Monday, with the aim of negotiating a ceasefire between Russia and Ukraine. According to Trump, Russia and Ukraine will "immediately start negotiations" towards a ceasefire, with the conditions for this ceasefire to be negotiated between the two parties. However, the Kremlin has clarified that a prisoner-of-war exchange must be completed prior to any negotiations, with a specific focus on a swap of 1,000 prisoners on each side.