Wall Street was set to fall about 1 percent at open on Tuesday on fresh concerns over fiscal problems in the euro zone ahead of bank repayments to the European Central Bank this week.

European banks must repay 442 billion euros ($545.5 billion) in emergency loans to the ECB on Thursday, leaving a potential liquidity shortfall of more than 100 billion euros in the financial system.

U.S. crude oil futures dropped 3.2 percent to $75.76 a barrel as investors turned against riskier assets.

We are definitely seeing a flight to safety. People are selling everything that is risky, said Tom Schrader, managing director of U.S. equity trading at Stifel Nicolaus Capital Markets in Baltimore.

S&P 500 futures lost 15.2 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 tumbled 107 points, and Nasdaq 100 futures slid 29 points.

The euro hit a lifetime low against the Swiss franc and an 8-1/2 bottom against the yen. The U.S. dollar <.DXY> rose 0.5 percent against a basket of major currencies.

The three-month LIBOR in euros, the price that European banks charge each other for short-term loans, rose to an 8-month high.

The Standard & Poor's/Case Shiller home prices indexes showed single-family home prices climbed unexpectedly in April from March. But investors were less enthusiastic as the rise was driven by a final sales push before tax credits expired, signaling that a sustained recovery have yet to emerge.

The Conference Board's June consumer confidence data is due at 10 a.m. EDT. Economists look for a reading of 62.8 versus 63.3 previously.

(Reporting by Angela Moon; editing by Jeffrey Benkoe)