U.S. stock index futures suggest a subdued opening to markets on Friday ahead of the release of U.S. unemployment data and nonfarm payroll reports, which could provide clues to the U.S. Federal Reserve's future monetary policy decision, even as the question of a U.S.-led attack on Syria recedes into the background for now.

Futures on the Dow Jones Industrial Average were down 0.08 percent, while futures on the Standard & Poor's 500 Index were flat and those on the Nasdaq 100 Index were up 0.11 percent.

All eyes will be on the unemployment figures for the month of August, which is expected to be released on Friday, at 8.30 a.m. EDT, as economists expect that the data could be a decisive factor in the U.S. Federal Reserve's decision-making process on winding down its $85 billion-a-month asset purchase program.

Economists expect the unemployment rate to remain unchanged at 7.4 percent.

The U.S. government's monthly nonfarm payroll report, which is due at 8:30 a.m. EDT, will also provide clues to the sustainability of the country's economic recovery and the future of the Fed's bond-buying program.

Economists polled by Bloomberg predict the nonfarm payroll report, which measures the change in the number of people employed during the previous month excluding the farming industry, to show a gain of 175,000 jobs in August, up from a gain of 162,000 jobs in July.

“A 200,000 increase in employment would be broadly consistent with the unemployment rate staying at 7.4%. As such, August’s Employment Report is likely to give the Fed the green light to start tapering QE3 at the meeting later this month,” Paul Dales, an economist with the Capital Economics, wrote in a research report.

The average hourly earnings report, which measures the change in the price businesses pay for labor not including the agricultural sector, is expected to move up by 0.2 percent in August, after declining 0.1 percent in July.

European markets were trading slightly down as investors opted for caution ahead of jobs data from the U.S. The Stoxx Europe 600 index was trading down 0.1 percent, London’s FTSE 100 was down 0.04 percent, Germany's DAX-30 was down 0.18 percent and France's CAC-40 was trading flat.

In Asia, most markets traded in positive territory. Australia’s S&P/ASX 200 gained 0.05 percent. In China, the Shanghai Composite index ended up 0.83 percent while Hong Kong’s Hang Seng Index gained 0.1 percent. Japan’s Nikkei ended down 1.45 percent. 

South Korea’s KOSPI Composite index added 0.19 percent and India’s BSE Sensex was trading up 1.46 percent in late-afternoon trade.