U.S. stock index futures pointed to a higher opening on Thursday as two reports on the labor market reinforced optimism that Friday's monthly payrolls data would be strong.

Retailers were also in focus as May same-store sales streamed in, with Thomson Reuters data indicating an average increase of 2.5 percent versus expectations of 2.6 percent. Target Corp rose 1.2 percent to $55 premarket, while Costco Wholesale Corp slid 1.6 percent to $58 as sales came in below estimates.

Private employers added 55,000 jobs in May, fewer than expected, compared with a revised gain of 65,000 in April, ADP Employer Services reported. Meanwhile, new jobless claims fell, but missed forecasts.

The revision in ADP is quite positive, but the data is mixed at best, said Dan Cook, senior market analyst at IG Markets in Chicago. However, the numbers are close enough to consensus that there's still quite a bit of optimism for tomorrow's number.

On Friday, the critical May non-farm payrolls report will be released, with economists looking for 513,000 non-farm jobs being added to the economy. U.S. President Barack Obama said he believed the report will show strong growth.

S&P 500 futures gained 5.1 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures rose 28 points, and Nasdaq 100 futures were up 3.5 points.

BP Plc made halting progress in its battle to siphon off oil belching from its ruptured wellhead in the Gulf of Mexico, but debris from the massive spill posed new threats to the shoreline. BP's U.S.-listed shares gained 3.6 percent to $39.03 before the bell.

General Electric Co and Japanese trading house Itochu Corp <8001.T> will invest in large wind and other renewable energy projects. GE, a Dow component, rose 0.5 percent at $16.43.

April durable goods, factory orders and the ISM non-manufacturing index are all due later Thursday.

Overseas markets were higher, with both European and Japanese stocks hitting two-week highs on optimism over the U.S. labor market.

U.S. stocks rose Wednesday, led by energy shares, as investors grabbed beaten-down shares.

(Editing by Jeffrey Benkoe)