Stock index futures pointed to a lower open on Monday, indicating the S&P 500 index will pull back after a five-week rally on concerns Greece may be unable to avoid a chaotic default as it tries to reach terms on a new bailout package.

Greece allowed another deadline to slip as political leaders failed to respond to terms for a new bailout from the European Union and International Monetary Fund. Greece needs the funds by March to meet big debt repayments.

German Chancellor Angela Merkel stepped up pressure on Greece, warning that time was running short for a deal to be struck.

The FTSEurofirst 300 <.FTEU3> index of top European shares dipped 0.2 percent. <.EU>

It's inevitable the risk profile that Greece represents is definitely going to cool the market tone, there is absolutely no way around that, said Peter Kenny, managing director at Knight Capital in Jersey City, New Jersey.

That lack of clarity, the protracted nature of this crisis and the fact that it simply will not go away, it's a bit unnerving to people who have seen the market tack on some very nice early year gains, and it forces people to want to be a little cautious.

S&P 500 futures fell 4.6 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 33 points, and Nasdaq 100 futures shed 9.75 points.

The S&P has rallied for five straight weeks on better-than-expected U.S. economic data, punctuated by Friday's solid employment report, pushing the index up 6.9 percent for the year.

Hasbro Inc fell 3.1 percent to $34.75 in premarket trade after the maker of Nerf foam toys and Monopoly board games reported a fourth-quarter profit just above analysts' lowered expectations.

Humana Inc posted a big rise in fourth-quarter profit, helped by higher membership in its Medicare plans for the elderly. The health insurer also slightly lifted its full-year earnings forecast. Its shares fell 3.2 percent to $87.24 premarket.

Other companies expected to post earnings include Yum Brands Inc , Pioneer Natural Resources Co
, Dun and Bradstreet Corp and Anadarko Petroleum Corp .

Through Friday, 283 companies in the S&P 500 had reported results, with 60 percent posting earnings that topped Wall Street expectations, a lower percentage than in recent quarters at this point of the reporting season.

Fidelity National Financial Inc agreed to buy O'Charley's Inc for $9.85 a share in a deal that values the casual dining chain at $221 million in cash. O'Charley's shares surged 42.3 percent to $9.85 premarket.

Boeing Co shed 1.5 percent to $75.20 after the airline maker said Sunday it discovered a problem related to the aft fuselage of its 787 Dreamliner planes. It said repairs will not affect production.

(Reporting By Chuck Mikolajczak; editing by Jeffrey Benkoe)