The IBEX 35 opened Tuesday in the red, pressured by renewed protectionist rhetoric in the United States and a pullback in technology stocks linked to artificial intelligence, all against a backdrop of heightened tensions in the Middle East.

Following the Supreme Court's decision to overturn his emergency tariffs, Donald Trump warned that he could impose higher duties if third countries stray from the recently agreed deals with Washington, indicating that the new tariffs would be implemented under Section 122 of the Trade Act of 1974. 

Adding to this in the United States was a wave of selling in software and other sectors, driven by fears of AI disruption and a bearish report from Citrini Research, which dampened investor sentiment and resulted in another negative session on Wall Street.

"(...) software sector valuations (in the United States) continue to adjust as AI begins to impact businesses previously considered defensive," noted analysts at Renta 4 brokerage.

These analysts highlighted that "IBM fell more than 13% after Anthropic announced that its Claude model is capable of working with and optimizing COBOL code, which the market interpreted as a potential risk to the modernization and maintenance business for legacy systems, a significant part of IBM's competitive advantage."

With volatility entrenched, the market is already looking ahead to Nvidia's results, due Wednesday, which will serve as a barometer for investor appetite in artificial intelligence. Analysts expect a 71% increase in earnings per share.

Meanwhile, frictions continued between the US and Iran ahead of the imminent reopening of nuclear talks, as a senior State Department official announced the withdrawal of non-essential staff and family members from the US embassy in Lebanon.

The day's agenda will be headlined by the traditional State of the Union address by US President Donald Trump before Congress, at a particularly delicate moment for his presidency.

At 0802 GMT, the IBEX 35 was down 0.34% (62.50 points) at 18,226.20, while the FTSE Eurofirst 300 slipped 0.24%.

On the earnings front, Telefónica rose 1.75% and Endesa advanced 3%, moving against the broader market trend. 

The financial sector showed a negative tone: Santander -1.34%, BBVA -0.77%, Caixabank -1.32%, Sabadell -1.20%, Bankinter -0.90%, and Unicaja Banco -1.02%.

Among non-financial heavyweights, Inditex slipped 0.07%, Iberdrola gained 0.38%, Cellnex fell 0.06%, and Repsol added 0.30%.

(Reporting by Tomás Cobos; editing by Benjamín Mejías Valencia)