Wall Street stocks opened lower on Monday as the market looks ahead to a Federal Reserve interest rate decision while digesting weekend elections that boosted far-right parties in Europe.

Just ahead of Wednesday's Fed announcement, investors will also take in US consumer price data that is expected to influence the central bank's outlook.

About 15 minutes into trading, the Dow Jones Industrial Average was down 0.2 percent at 38,736.25.

The broad-based S&P 500 also declined 0.2 percent to 5,334.62, while the tech-rich Nasdaq Composite Index lost 0.3 percent at 17,083.24.

Bourses in Europe were broadly lower -- along with the euro currency -- after far-right parties performed well in EU elections, prompting French President Emmanuel Macron to call a snap parliamentary poll.

"The snap election called in France has added to the uncertain tides swirling around financial markets," said Susannah Streeter, head of money and markets at stockbroker Hargreaves Lansdown.

Among individual companies, Southwest Airlines jumped 6.6 percent following a Wall Street Journal report that activist fund Elliott Investment Management took a stake of nearly $2 billion in the struggling airline.

Apple dipped 0.4 percent just ahead of its Worldwide Developers Conference where the tech giant is expected to elaborate on its artificial intelligence plans.