European equity markets were set to open on a weaker note on Monday, influenced by escalating global trade tensions that affected investor confidence. President Donald Trump of the United States announced his decision to increase tariffs on steel and aluminum imports to 50%, starting June 4. This move provoked criticism from several key trading partners. The European Union expressed its disapproval, stating that the tariff increase jeopardizes efforts to achieve a "negotiated solution" in the ongoing trade dispute. Concurrently, China dismissed Trump's allegation that it had violated a trade agreement brokered in Geneva the previous month, adding further uncertainty regarding a possible near-term conversation between Trump and Chinese President Xi Jinping. In premarket activity, futures suggested a subdued opening, with Euro Stoxx 50 futures declining by 0.4% and Stoxx 600 futures down by 0.3%.