Stocks were set to fall at the open on Wednesday as FedEx warned about higher costs, housing starts fell to a five-month low and new concerns surfaced over Spain's fiscal problems.

Housing starts fell more than expected in May as a homebuyer tax credit expired, a government report showed.

The premium that investors demand to hold 10-year Spanish government bonds rather than euro zone benchmark German Bunds hit a euro lifetime high, even as the European Commission denied a report that a liquidity plan being set up for Spain.

Further weighing on investor sentiment, FedEx Corp said costs would constrain 2011 earnings and cell phone maker Nokia said profits at a key unit would be weaker than expected this quarter and in 2010. and

FedEx shares fell 2.3 percent to $81.07 in premarket trading while New York-traded Nokia shares tumbled 9.8 percent to $8.86.

The housing start numbers weren't great, and you have the concerns about Spain and other euro zone countries' debt situation, said Kurt Brunner, portfolio manager at Swarthmore Group in Philadelphia.

He said the Nokia and FedEx news painted a picture of an economic recovery that could be slower and more difficult.

S&P 500 futures fell 5.7 points and were below 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 lost 46 points, and Nasdaq 100 futures dropped 8.25 points.

The S&P 500 closed above its 200-day simple moving average on Tuesday, and its ability to stay above that level could be tested.

The euro, used in the current climate to assess investors' risk appetite, briefly hit a two-week high before dropping against the U.S. dollar.

Energy stocks will be in the spotlight as U.S. President Barack Obama meets with BP Plc executives later Wednesday and demands the company set aside billions of dollars to pay damages from the Gulf of Mexico oil spill.

Bank of America-Merrill has ordered traders not to enter into oil trades with BP that extend beyond June 2011, a source told Reuters.

BP's New York-traded stock lost 4 percent to $30.13 premarket.

Wall Street surged on Tuesday as investors went on a buying spree, pushing the S&P 500 into positive territory for 2010.

(Reporting by Rodrigo Campos; editing by Jeffrey Benkoe)