U.S. stock index futures edged higher on Wednesday ahead of the Federal Reserve's monetary policy decision, while the Israel-Iran conflict entered its sixth day, with new missile strikes launched from both sides.

The Fed is expected to hold rates steady as it continues to observe the effects of President Donald Trump's tariffs.

Investors are nearly unanimous in expecting the Federal Reserve to keep interest rates on hold Wednesday, in a range of 4.25% to 4.5%. The chart below shows how the central bank has steered policy since the turn of the century,