US benchmark equity indexes ended lower Thursday as President Donald Trump warned significant import duties could befall the European Union's alcohol products and cooling producer prices failed to inspire confidence among investors.

* President Trump threatened to impose a 200% tariff on imports of European alcoholic products in response to retaliatory duties announced by the EU on Wednesday. The US administration's 25% global levies on steel and aluminum imports took effect that day, prompting a reaction from the EU and fueling concern a protracted trade war could be starting.

* The US producer price index remained unchanged in February, compared with an upwardly revised 0.6% increase in January, the Bureau of Labor Statistics said Thursday. The print lagged the 0.3% growth estimate in a survey compiled by Bloomberg. Year over year, overall producer prices were up 3.2% last month versus a 3.7% rise in January, trailing the 3.3% rate estimated by the Street.

* April West Texas Intermediate crude oil closed down $1.07 to settle at $66.61 per barrel, while May Brent crude, the global benchmark, was last seen down $1.08 to $69.87 as the International Energy Agency said it expects higher global demand this year to be accompanied by rising inventories, while cautioning its outlook is clouded by US trade wars.

* Intel (INTC) appointed semiconductor industry veteran Lip-Bu Tan as its new chief executive, effective March 18. Tan, who previously served as CEO of Cadence Design Systems (CDNS), will succeed interim co-CEOs David Zinsner and Michelle Johnston Holthaus. The chipmaker's shares surged 14%.

* Adobe (ADBE) shares slumped over 14%. A "clearer roadmap" is needed to dispel "apathy" surrounding the stock even after the software company's Q1 results topped estimates, a Morgan Stanley note said.