US retail behemoth Walmart Thursday reported a 1.3 percent increase in quarterly earnings, but slashed its full-year financial outlook amid tight consumer spending in the United States and abroad. Earnings for the second quarter ended July 31 came in at $4.07 billion on revenues of $116.22 billion, up from the year-ago level of $4.02 billion on $113.52 billion. But comparable store sales in US Walmart stores, the company\'s biggest retail division, dipped 0.3 percent. Walmart executives pointed to higher US payroll taxes, which also dragged on earnings in the previous quarter. In addition, Walmart said international consumers are also watching their spending. \"The retail environment remains challenging in the US and our international markets, as customers are cautious in their spending,\" said Walmart chief financial officer Charles Holley. Walmart trimmed its forecast for 2013 net sales growth to between 2 and 3 percent from a previous projection of 5 to 6 percent growth. The company also forecast that full-year earnings would be between $5.10 and $5.30 per share, versus the previous range of $5.20-$5.40. \"This revision reflects our view of current global business trends, and significant ongoing headwinds from anticipated currency exchange rate fluctuations,\" Holley said. Walmart reported $1.24 per share for the second quarter, compared with analyst expectations of $1.25 per share. The company said the figure was hit by one cent due to an unspecified charge in Walmart International. Revenues came in $2.35 billion shy of the $118.57 billion forecast by analysts. Walmart shares are down 1.9 percent in pre-market trading.