The U.S. stock index futures point to a lower open Tuesday as investor sentiment was weighed down by the fear that the deepening global economic condition would affect the corporate earnings.

The futures on the Dow Jones Industrial Average were down 0.19 percent, the futures on the Standard & Poor's 500 Index were down 0.39 percent and those on the Nasdaq 100 Index were down 0.14 percent. 

Investors will continue to focus on the stream of earnings to be reported this week, which will present further indications on whether there is any improvement in the health of the U.S. firms or not. Market players will be keenly watching the earning reports from United Parcel Service, 3M, Facebook and Xerox Corporation to be announced Tuesday.

On Monday, the U.S. markets rose marginally as investors remained watchful waiting for a slew of corporate earnings to be reported this week, which will present a clearer picture about the impact of the weakening global economy on the business conditions.

Caterpillar Inc reported Monday that the company’s third quarter sales and revenues rose 5 percent to $16.445 billion compared to $15.716 billion in the same period last year. For the third quarter, the company, which is the world's largest maker of tractors and excavators, reported $2.54 profit per share, up from $1.71 in the same period last year. However, the company cut the forecast for 2012, citing the weakening global economic conditions.

The Dow Jones Industrial Average rose 0.02 percent, the S&P 500 Index was up 0.04 percent and the Nasdaq Composite Index advanced 0.38 percent.

European markets remained in a tight range Tuesday as investors were cautious amid the revival of the concerns about the debt burden faced by the euro zone with persisting financial instability in Greece and Spain. London's FTSE 100 was up 1.49 points, Germany's DAX 30 index rose 4.96 points and France's CAC 40 dropped 5.58 points.

Asian stocks were mixed following the global cues. Markets in Hong Kong are closed for a holiday. Japan's Nikkei Stock Average rose 3.54 points and South Korea’s KOSPI Composite Index declined 14.78 points.