(Reuters) -U.S. stock index futures edged lower on Friday as market participants continued to grapple with the ramifications of tariffs, with FedEx being the latest company to lower its full-year forecasts due to economic uncertainty.

FedEx fell 7.2% in premarket trading, while peer UPS slipped 1.5%. Delivery firms are often seen as a barometer for the global economy given their involvement in a wide range of industries.

The Dow Jones Transport Index, often regarded as a key indicator of U.S. economic heath, has fallen nearly 18% from its all-time peak and was poised to record its longest weekly losing streak in over a year.

Persistent anxieties that an ongoing global trade war could upend the economy and squeeze corporate profitability have spiked market volatility recently and investors have been cautious about riskier assets.

Markets now await President Donald Trump's plans on reciprocal and sectoral tariffs that are expected to take effect in early April.

Commenting on the impact of tariffs, Commerzbank analysts wrote, "this only serves to create uncertainty among companies, which are increasingly putting their plans for new jobs and investment on hold."

At 7:18 a.m. ET, Dow E-minis were down 119 points, or 0.28%, S&P 500 E-minis were down 15.5 points, or 0.26% and Nasdaq 100 E-minis were down 74.5 points, or 0.37%.

However, on a weekly basis the benchmark S&P 500 index is set to log a 1.1% gain, rising for the first time in five weeks. It was also on track to snap its longest weekly losing streak in over a year.

The blue-chip Dow was set to notch its biggest weekly rise in over two months, if gains hold.

Earlier in the week, investors took some comfort from Federal Reserve Chair Jerome Powell's comments who said that the overall economy was on solid footing. However, he warned that the decision to leave interest rates unchanged stemmed from a cloudy outlook on the impact from Trump's policies.

This week also witnessed other central banks including the Bank of Japan and the Bank of England adopting a cautious tone, underscoring the unpredictable economic outlook attributed to escalating trade tensions.

Traders are pricing in approximately 70 basis points of rate cuts from the Fed this year, with a 70% likelihood of a 25 basis point cut at the upcoming June meeting, according to data compiled by LSEG.

Among other movers, Nike fell 6.5% after the sports apparel maker projected a sharper decline in fourth-quarter revenue than analysts had anticipated.

Micron Technology ( MU ) swung between gains and losses and was last down 3.8%. The chip maker forecast third-quarter revenue above Street estimates.

Growth stocks, which bore the brunt of the recent market rout, slipped. Apple ( AAPL ) lost 0.7%, Amazon.com ( AMZN ) dipped 0.2%, while Nvidia ( NVDA ) lost 0.8%. The tech-heavy Nasdaq is on track to record its longest weekly losing streak in nearly three years.

Investors will closely monitor insights from policymakers including New York Fed President John Williams and Chicago Fed President Austan Goolsbee later in the day.

Friday's session also marks the simultaneous expiry of quarterly derivatives contracts tied to stocks, index options and futures, also known as "triple witching".