* Global markets higher on Greece deal optimism
* Existing home sales data expected
* Nasdaq hits new record high
* Cigna shares up after rebuffing Anthem's $47 bln offer
* Indexes up: Dow 0.69 pct, S&P 0.7 pct, Nasdaq 0.7 pct (Updates to open)
By Tanya Agrawal
June 22 (Reuters) - Wall Street opened higher on Monday, with the Nasdaq Composite index hitting a new record high, after optimism grew that Greece may be able to strike a last-minute deal with its international creditors to avert a default.
Nasdaq touched a high of 5,156.98, surpassing the previous high of 5,143.32 it had set last week.
Eurogroup chairman Jeroen Dijsselbloem said proposals from Greece were positive and could be the basis of an agreement later this week.
EU Economic Commissioner Pierre Moscovici earlier said he was "convinced" that euro zone leaders who held an emergency meeting in Brussels would find a way out of the Greek crisis.
Athens needs fresh funds to avoid defaulting on a $1.8 billion debt repayment to the International Monetary Fund on June 30, and a possible exit from the euro zone.
Global stocks were higher on Monday with European shares hitting their highest level in over a week.
"The Greece situation has a psychological effect on investors," said Peter Cardillo, chief market economist at Rockwell Global Capital in New York.
"If Greece were to exit the euro, it raises speculation on the future of its peripheral nations and so if we do see a breakthrough in the talk, expect the markets to rally."
U.S. stocks closed lower on Friday as Greek worries weighed but the three major indexes were higher for the week on hopes that the U.S. Federal Reserve's planned rate hike will be slower than previously anticipated.
Sales of previously owned homes likely recovered last month, data from the National Association of Realtors is expected to show. Economists expect existing home sales to have jumped 4.4 percent to a 5.26 million unit-rate in May. The data is expected at 10:30 a.m. ET (1430 GMT)
At 9:54 a.m. ET the Dow Jones industrial average was up 124.48 points, or 0.69 percent, at 18,140.43, the S&P 500 was up 14.87 points, or 0.7 percent, at 2,124.86 and the Nasdaq Composite was up 35.78 points, or 0.7 percent, at 5,152.78.
Nine of the 10 major S&P 500 sectors were higher with the healthcare index leading the gains.
The market was also boosted by M&A chatter over the weekend as companies rush to make the best of the zero-rate interest environment before an expected hike this year.
Cigna's shares rose 6.2 percent to $164.79 after the health insurer rebuffed Anthem's $47 billion merger proposal on Sunday. Anthem was up 3.9 percent to $171.41.
Humana was up 1.4 percent at $205.15 as sources said Cigna along with Aetna are participating in an auction to acquire the company. Aetna was up 4 percent at $129.03.
Williams Cos jumped 24.1 percent to $60 after Energy Transfer Equity confirmed it had made a $48 billion unsolicited bid for the natural gas pipeline company. Williams rejected the offer as too low.
Fitbit soared 12.8 percent to $36.64, building on last week's impressive IPO, which valued the maker of wearable fitness-tracking devices at $6.5 billion.
Advancing issues outnumbered decliners on the NYSE by 2,025 to 745. On the Nasdaq, 1,758 issues rose and 695 fell.
The S&P 500 index showed 45 new 52-week highs and one new lows, while the Nasdaq recorded 145 new highs and 8 new lows. (Editing by Don Sebastian)