Major U.S. stock indices opened higher on Wednesday, with heightened investor anticipation surrounding the Federal Reserve's decision on interest rates scheduled for later in the day.

Concerns regarding trade policies and their potential impact on the economy continue to weigh on investor sentiment.

The Dow Jones Industrial Average climbed 587.6 points, or 1.41%, reaching 42,135.04 points.

The Standard & Poor's 500 index opened with a gain of 97.68 points, or 1.74%, standing at 5,703.95 points, while the Nasdaq composite increased by 397.99 points, or 2.18%, to 17,881.32 points.

European equities also recorded slight gains following a positive trading session on the previous day.

The Stoxx 600 European index rose by 0.2%, continuing its upward trend for the fourth consecutive session.

In Europe, shares in the industrial and energy sectors constituted significant contributors to the main index's performance.

The retail sector within the Stoxx 600 saw a notable increase of 1.6%, marking the best performance among various sectors.

Conversely, the telecommunications sector closed at its lowest levels.

Recent data revealed that inflation rates in the Eurozone were below initial estimates, alleviating fears that unexpectedly strong price pressures might hinder the European Central Bank from pursuing further interest rate cuts.