* Dollar gains broadly, traders adjust short positions
* Dollar/yen up nearly 1 percent on day to near 3-wk high
* Sterling suffers after BoE report
(Adds comment, details, updates throughout; previous SYDNEY/SINGAPORE)
By Naomi Tajitsu
LONDON, Sept 21 (Reuters) - The dollar rose broadly on Monday, extending its pullback from a one-year low against the euro as traders continued to trim short positions in the U.S. currency following broad losses so far this month.
Against the yen, the dollar rose nearly a full percent on the day after speculative flows pushed the U.S. currency higher in quiet trade in Asia, where markets in Japan and Singapore were closed for holidays.
The pound continued to come under selling pressure, hitting a five-month low against the euro after the Bank of England said the pound's long-run sustainable exchange rate may have fallen due to an increased focus on Britain's economic imbalances following the global credit crisis..
Analysts said mounting short positions in the dollar may be a signal that it will recover some of its recent losses this week.
"There's already a lot of long euro/dollar positions in the market so it's difficult to push the pair higher," said Lutz Karpowitz, currency strategist at Commerzbank in Frankfurt.
Data from the Commodity Futures Trading Commission showed that currency speculators last week raised short dollar positions -- essentially bets that the U.S. currency will depreciate -- to their highest since March 2008.
Some said the Federal Reserve's Wednesday policy decision may also boost the dollar.
By 0738 GMT, the euro had slipped 0.3 percent to $1.4662, easing from $1.4768 hit late last week, its strongest since September 2008.
The dollar was up 0.8 percent at 92.00 yen, near the day's high around 92.20 yen touched in early European trade.
RESISTANCE BROKEN
Traders said leveraged names and momentum funds took advantage of thin Tokyo trade to trigger stop-loss orders above 91.60 yen, pushing the pair through technical resistance at 91.80 yen.
Sell orders from Japanese exporters were seen above 92.50 yen as Tokyo markets are closed through Wednesday for national holidays.
Against a currency basket, the dollar rose half a percent to 76.798, off a one-year low of 76.01 hit last week.
Sterling was under broad selling pressure, pushing the euro up more than 0.2 percent on the day to 90.79 pence, its highest since late April.
Against the dollar, it was down 0.6 percent at $1.6175, near $1.6134 hit earlier in the day for its weakest level in nearly three weeks.
With few major economic events or data scheduled in the European session on Monday, participants expected trade to be driven by technical factors and positions adjustments.
The Fed begins its monthly policy meeting on Tuesday, and is widely expected to keep the Fed funds rate chained near zero, but some analysts said that the dollar may appreciate if the central bank expresses more optimism about the U.S. economy. (Editing by Patrick Graham)