U.S. stock futures edged lower Tuesday morning as investors brace for Federal Reserve Chairman Kevin Warsh's remarks that could signal the next move on interest rates. Warsh joins European Central Bank, Bank of England and Bank of Canada leaders at a Sintra, Portugal conference, with markets parsing every word for monetary policy direction.

Treasury yields climbed further following Monday's robust job openings data, reinforcing expectations for continued rate tightening. The yield gains come after stocks capped a strong quarter with solid gains, putting pressure on futures contracts tied to major indexes. Traders are also monitoring oil markets closely, where Brent crude holds just below $73 a barrel amid Middle East tensions.

President Trump's apparent willingness to extend Iran negotiations beyond the August 18 deadline provides some relief to energy markets, reducing fears of sudden supply disruptions. Meanwhile, the Japanese yen slid to a fresh 40-year low against the dollar, triggering speculation about potential official intervention to stem the currency's decline.

The market's focus remains squarely on Warsh's testimony, with investors looking for clarity on whether the Fed will maintain its aggressive stance or signal a pause. Any shift in tone could reshape trading strategies heading into the second half of the year.