* Greek worries remain key market focus
* Focus on EU summit next week to see if Greece gets aid
* Euro/Swiss franc tumbles to 17-month low (Adds comment, updates prices)
By Gertrude Chavez-Dreyfuss
NEW YORK, March 19 (Reuters) - The euro fell to its lowest level against the dollar in more than two-weeks on Friday, pressured by persistent worries about Greece's debt problems as traders waited to see if the country can secure aid from euro zone members at a summit next week.
The European single currency, on track for its worst weekly performance since late January, had weakened on Thursday after a published report saying the country saw limited prospects for euro zone assistance heightened uncertainty about Greece's ability to service its debts.
"The tensions surrounding Greece are escalating. This whole IMF situation has become a game of brinkmanship and the whole uncertainty is undermining the euro," said Michael Woolfolk, senior currency strategist, at BNY Mellon in New York.
Greece said on Thursday it could not achieve promised deficit cuts if borrowing costs remained high, and it might have to turn to the International Monetary Fund. Greece, however, dismissed a news report that it was planning to turn to the global lender as soon as early April if European Union leaders do not agree on a rescue plan next week.
"Greece is doing all the right austerity measures, but it is paying 300 basis points above German bunds and that's just not possible. So it's creating an untenable conflict among the members," said Boris Schlossberg, director of FX research at GFT in New York.
The premium investors demand to buy 10-year Greek government bonds over German benchmarks continued to rise on Friday.
In midday New York trading, the euro slid 0.6 percent on the day to $1.3515 after hitting its lowest level in more than two weeks at at $1.3502, according to Reuters data.
"I really don't see any support for the euro. We may have to test that low below $1.3450 in the near term," Woolfolk said, adding investors also need to watch the Dow industrials stock index.
"The Dow is down and that reflects risk aversion," he said. "The Dow is due for profit taking and now is a good time because there are renewed European worries going into the weekend," suggesting that the euro would fall further if the Dow declines.
The euro was down 0.2 percent against the Swiss franc to trade at 1.4367 francs. Earlier, it fell to 1.4320 francs, its weakest since October 2008 in the aftermath of hawkish comments from a Swiss National Bank official.
SNB board member Jean-Pierre Danthine said on Thursday that Swiss firms and consumers should prepare for rising borrowing costs and exchange rates determined by the market as interest rates could not stay low forever.
Traders are focusing on the 1.4300 area, the record low, as the next support level. Options structures were said to be prevalent at that level.
The SNB's statement last week made no change to its pledge to counter excessive gains in the franc as it continues to appreciate against the euro.
The dollar was broadly supported, up 0.7 percent against a currency basket to 80.814, and traded at 90.51 yen against the Japanese currency, up 0.2 percent on the day.
Sterling fell 1.5 percent versus the dollar to $1.5021, undermined by remarks from Bank of England policy maker Andrew Sentance that there was some risk of a double-dip recession in the UK.
The Canadian dollar earlier gained after Canadian core inflation unexpectedly rose in February. It earlier hit a 20-month high versus the U.S. dollar at C$1.0062, but the greenback recovered to trade up 0.1 percent at C$1.0153. (Editing by Leslie Adler)