* Dollar wallows near 2-1/2-yr low vs euro, 7-week trough vs yen
* Dollar struggles after weak US ISM data
* Pound near 9-mth low vs euro after BoE delivers dovish message (Adds details and quotes, updates prices)
By Shinichi Saoshiro
TOKYO, Aug 4 (Reuters) - The dollar struggled near a 2-1/2-year low against the euro and a seven-week trough versus the yen on Friday in the wake of weak U.S. data, with traders awaiting the closely watched non-farm jobs report later in the session for potential relief.
The dollar index against a basket of six major currencies was 0.1 percent lower at 92.766, poised to lose about 0.6 percent on the week during which it fell to a 15-month low of 92.548.
The ailing greenback has come under pressure this week from fresh political turmoil in Washington as well as largely uninspiring U.S. economic data, which have added to uncertainty about the pace of future Federal Reserve policy tightening.
The market received a fresh dose of both factors overnight.
Data showed a much sharper-than-expected slowdown in growth in the services sector, while it was reported that a grand jury will investigate allegations of Russian meddling in the U.S. election.
Beleaguered dollar bulls looked to the U.S. jobs report due at 1230 GMT to turn its fortunes around, at least in the short term.
Economists polled by Reuters expect U.S. employers to have added 183,000 jobs in July, down from 222,000 in June.
The euro added 0.1 percent to $1.1879, within striking distance of $1.1910, its highest since January 2015 scaled midweek.
The dollar was steady at 110.085 yen after touching 109.855 overnight, its lowest since mid-June.
"Expectations for the Fed hiking interest rates within the year are already less than 50 percent and the figure could drop further if the jobs report disappoints, taking dollar/yen towards 109.00," said Yukio Ishizaki, senior currency strategist at Daiwa Securities.
Fed funds futures implied traders saw a roughly 44 percent chance of a Fed rate hike in December, according to CME Group's FedWatch tool.
"While bargain hunting by Japanese institutional investors is preventing dollar/yen from sliding too far below 110.00 yen, there is also significant demand for the yen stemming from its gains against the pound and the Canadian and Australian dollars," Ishizaki said.
Sterling took a battering overnight after the Bank of England voted 6-2 to keep interest rates at current record lows and lowered its forecasts for growth, inflation and wages, disappointing investors who expected a more hawkish message.
The pound was last at 90.43 pence per euro after retreating to a nine-month low of 90.485 pence overnight. It stood little changed at $1.3140 after losing 0.7 percent the previous day.
Against the yen, the pound extended losses from Thursday, when it slid 1.2 percent, to touch an 11-day low of 144.33 .
Expectations had grown recently that the BoE would join its peers in taking a step towards normalising monetary policy, so the message delivered by the central bank was seen as a big setback for sterling.
"The pound is on track to continue losing ground against other major currencies. And against the euro, we could see it eventually fall below the low marked during its 'flash crash' last October," said Makoto Noji, senior strategist at SMBC Nikko Securities.
The pound had suffered a steep drop to around 94.00 pence per euro early last October when investors were grappling with the prospect of a hard Brexit. (Reporting by Shinichi Saoshiro; Editing by Eric Meijer, Lisa Twaronite and Kim Coghill)