* Investors watching situations in Greece, Ukraine
* S&P 500 coming off record closing high
* Crude oil rises for third straight session
* Dow down 7 pts, S&P down 2.5 pts, Nasdaq up 5.25 pts
By Ryan Vlastelica
NEW YORK, Feb 17 (Reuters) - U.S. stock index futures were unchanged on Tuesday, the first trading session after the S&P 500 closed at an all-time record, although investors continued to watch uncertain situations overseas.
* Equities have been in an uptrend lately, with major indexes notching a second straight week of solid gains last week. Much of that advance came on signs of progress for a debt deal in Greece, as well as reduced tension between Russia and Ukraine.
* While both situations appeared less stable over the long weekend, when the U.S. stock market was closed for Presidents Day, investors were not spurred to sell, supported as crude oil rose for the third straight day.
* In Europe, European Union finance ministers piled pressure on Greece to remain in an international financial rescue program after talks collapsed on Monday. U.S.-listed shares of the National Bank of Greece fell 15 percent to $1.37 in heavy premarket trading.
* Separately, pro-Russian separatists said they would not carry out an agreement to pull back heavy guns in eastern Ukraine, putting the state of a shaky peace deal in question.
* While the United States has little direct exposure to either Greece or Ukraine and Russia, any breakdown in the situations could lead to continued volatility in Europe, a major trading partner.
* Crude oil rose 0.8 percent to $53.24, while Brent crude was up 1.2 percent at $62.16 on expectations that lower prices may prompt a slowdown in U.S. output. Separately, bombings by Egypt against Islamic State targets in Libya raised concerns about a threat to Middle East supplies.
* Corporate earnings have also supported recent equity gains. Of the 391 S&P 500 companies that have reported results so far this quarter, about 71.1 percent have topped profit expectations, according to Thomson Reuters data, while 57.5 percent have beaten on revenue. The earnings growth rate for the quarter is 6.6 percent, down from the 11.2 percent expected on Oct. 1, but up from 4.2 percent expected on Jan. 1.
* In company news, Micron Technology rose in premarket trading the day after both RBC and Jefferies raised their price target on the stock.
Futures snapshot at 6:55:
* S&P 500 e-minis were down 2.5 points, or 0.12 percent, with 196,213 contracts changing hands.
* Nasdaq 100 e-minis were up 5.25 points, or 0.12 percent, in volume of 37,173 contracts.
* Dow e-minis were down 7 points, or 0.04 percent, with 40,253 contracts changing hands. (Editing by Lisa Von Ahn)