KYIV: The US national security adviser warned Ukraine’s leader to stop hurling “insults” at Donald Trump, as pressure built Friday on Volodymyr Zelensky to sign away precious mineral rights in exchange for Washington’s help defending against Russia. Tensions between Trump and Zelensky over the proposed mineral deal — which Kyiv has rejected — and Washington’s outreach to Moscow have exploded this week in a series of barbs traded at press conferences and on social media.