US STOCKS-US stock futures slide as tariff rally eases, UnitedHealth slips

May 15 (Reuters) - U.S. stock index futures slipped on Thursday as a rally fueled by the U.S.-China tariff truce appeared to ease, while UnitedHealth fell after a report of a DoJ investigation into the health insurer.

Investors will also focus on comments from Federal Reserve Chair Jerome Powell due later in the day, while earnings update from Walmart WMT.N will give further evidence on the health of the U.S. consumer. The retailer's shares inched up in premarket trading.

UnitedHealth Group UNH.N dropped 4.7% after the Wall Street Journal reported the U.S. Department of Justice is carrying out a criminal investigation into the health insurer for possible Medicare fraud.

The company said it has not been informed of criminal probe by federal prosecutors.

At 05:08 a.m. ET, Dow E-minis YMcv1 were down 169 points, or 0.4%, S&P 500 E-minis EScv1 were down 37.75 points, or 0.64% and Nasdaq 100 E-minis NQcv1 were down 179.25 points, or 0.84%.

Investors will look out for comments from Powell later in the day after some Fed officials said earlier this week that policymakers are leaving interest rates unchanged while they try to assess how tariffs and trade negotiations will affect prices and the economy.

A reading of producer prices and retail sales for April, along with weekly jobless claims data are due at 8:30 a.m. ET.

The data comes at the heels of a tame consumer prices reading earlier this week, which showed consumer prices rebounded moderately last month.

In results-driven moves, Cisco Systems CSCO.O gained 4.7% after the networking equipment maker raised its annual forecasts and named Mark Patterson as its new CFO.

Stocks have been on a roller-coaster ride this week. They rallied on Monday and Tuesday after the United States and China hit pause for 90 days on their fierce tariff dispute.

These initial gains saw the S&P .SPX turn positive on a year-to-date basis for the first time since late February, though it still remains about 4% away from its all-time highs.

However, stocks paused in the last session as markets awaited fresh catalysts, with the S&P 500 notching marginal gains, while the Dow .DJI ended lower.

Most megacap and growth stocks, which have seen strong gains so far this week, slipped, with Nvidia NVDA.O falling 2.3% and Tesla TSLA.O shedding 3.3%.

Other major movers included Foot Locker FL.N, which soared 70.6% after the Wall Street Journal reported that rival Dick's Sporting Goods DKS.N was nearing a deal to buy the footwear retailer for about $2.3 billion.

Top oil producer Chevron CVX.N and Exxon Mobil XOM.N dropped about 1.5% each as oil prices slid more than 3% on expectations for a U.S.-Iran nuclear deal that could result in sanctions easing.

U.S. President Donald Trump - who is on a four-day tour of the Gulf region - said that the United States was getting very close to securing a nuclear deal with Iran, and Tehran had "sort of" agreed to the terms.