TREASURIES-U.S. debt prices rally but supply looms next week

* Stocks' slide feeds safe-haven bid for Treasuries

* Nervousness about Greece developments persists

* U.S. durable goods orders higher than forecast in May
(Adds comment, recasts lead, updates prices, changes byline)

By Emily Flitter

NEW YORK, June 24 (Reuters) - U.S. Treasury prices extended
their rally on Friday as more money flowed out of European
bonds and equities and into safe-haven U.S. debt, but traders
said prices could fall next week ahead of scheduled auctions.

The Treasury Department plans to sell $99 billion in new
debt on Tuesday, Wednesday and Thursday. Selling ahead of the
auctions to lower auction prices and raise yields could
overpower the safety bid, which remained strong going into the
weekend.

"There's so much uncertainty, even beyond Greece, in Europe
that we're getting yields that are low despite the fact that we
have nearly $100 billion of twos, fives and sevens to sell next
week," said David Coard, head of fixed income sales and trading
at Williams Capital in New York.

"I think the street is going to do its level best to get a
concession, because the only way these yields are justified is
if we continue to have news out of Europe that creates this
safe-haven buying. The economy is sluggish but it's not falling
out of bed and unless it were falling out of bed there would be
no justification for these yields."

Two year notes US2YT=RR continued their rally for an 11th
straight week, the longest in more than 30 years, coming close
during trading on Friday to a record intraday low touched on
Nov. 4, 2010 at 0.3200 percent.

Two year notes closed unchanged in price from Thursday and
yielding 0.346 percent.

Nervousness about the Greek debt situation potentially
becoming "contagious" and affecting the euro zone and global
financial system whetted investors' appetite for Treasuries.

"As has been the case lately, domestic economic numbers are
playing second fiddle to the events overseas," said Kevin
Giddis, president of fixed-income capital markets at Morgan
Keegan. "Bonds are strengthening as investors seek 'insurance'
from unfavorable developments in Greece over the weekend."

Concerns that the Greek parliament could reject new
austerity measures hurt riskier assets in general and helped
safe-haven assets like U.S. Treasuries, analysts said. For more
see [ID:nN1E75N0B4].

The Greek parliament is scheduled to vote on the austerity
plan on Wednesday and Thursday. For a timeline see
[ID:nLDE75K1EC].

The benchmark 10-year U.S. Treasury note US10YT=RR rose
11/32, erasing an earlier loss. Its yield eased to 2.87 percent
from 2.91 percent late on Thursday, closing at its lowest point
since Nov. 30, 2010.

The three major U.S. stock indexes .DJI.SPX.IXIC,
meanwhile, were down around 1 percent each.

In the middle of the maturity curve, the five-year note
US5YT=RR was up 11/32, its yield slipping to 1.38 percent
from 1.46 percent on Thursday.

The Federal Reserve bought $4.578 billion in U.S.
Treasuries with maturities ranging from April 15, 2014, to May
15, 2015. The purchases were part of the U.S. central bank's
second phase of large-scale asset purchases, known as QE2,
intended to facilitate lending and encourage economic growth.

U.S. three-month bills US3MT=RR yielded 0.015 percent and
six-month bills US6MT=RR yielded 0.071 percent.

On the economic data front, the Commerce Department said
U.S. durable goods orders rose 1.9 percent after a revised 2.7
percent drop in April. Non-defense capital goods orders
excluding aircraft, a closely watched proxy for business
spending, rebounded to increase 1.6 percent last month after a
revised 0.8 percent fall in April.

The annual rate of first-quarter U.S. growth was revised
upward to 1.9 percent from a previously estimated 1.8 percent,
according to the government's final estimate.
(Additional reporting by Ellen Freilich, Richard Leong and Dan
Bases; Editing by James Dalgleish)