(Updates with early U.S. markets activity, changes dateline, previous LONDON)
* U.S. stocks down in early trading
* Treasury yields slip for third straight day
* Oil falls on uncertainty over future OPEC+ output
By Caroline Valetkevitch
NEW YORK, June 30 (Reuters) - Stocks on global indexes were sharply lower on Thursday and Treasury yields slid after U.S. data showed consumer spending rose less than expected in May while price pressures were still strong enough to leave the Federal Reserve on its aggressive policy-tightening path.
The U.S. benchmark S&P 500 was set to register its worst first six months since 1970, while MSCI's gauge of stocks across the globe was set for its worst first half of a year on record.
The Commerce Department report on Thursday showed U.S. consumer spending rose less than expected in May, and suggested inflation had probably peaked, while higher prices forced cutbacks on some purchases.
Rising interest rates and tight financial conditions have been fueling worries of a recession.
"Inflation is not something that we don't have to worry about anymore. It is expected to be with us for quite some time," said Sam Stovall, chief investment strategist at CFRA in New York.
Central bank chiefs from the U.S. Federal Reserve, the European Central Bank and the Bank of England met in Portugal this week and voiced their renewed commitment to control inflation no matter what pain it caused.
The Dow Jones Industrial Average fell 247.64 points, or 0.8%, to 30,781.67, the S&P 500 lost 26.34 points, or 0.69%, to 3,792.49 and the Nasdaq Composite dropped 103.29 points, or 0.92%, to 11,074.60.
Since the start of the year, the S&P 500 has lost roughly 20%, its worst first-half of a year since 1970.
The pan-European STOXX 600 index lost 1.50% and MSCI's gauge of stocks across the globe shed 0.95%.
The Fed's hawkishness and an investor desire for liquidity in difficult times have helped support the U.S. dollar.
The dollar index fell 0.238%, with the euro up 0.27% to $1.0467.
In Treasuries, benchmark 10-year notes last rose 27/32 in price to yield 2.9944%, from 3.093% late on Wednesday.
Oil prices fell as OPEC+ confirmed it would increase output in August only as much as previously announced.
U.S. crude recently fell 2.79% to $106.72 per barrel and Brent was at $115.16, down 0.95% on the day.
Spot gold dropped 0.3% to $1,812.43 an ounce.
(Reporting by Caroline Valetkevitch in New York Additional reporting by Thomas Wilkes in London and Wayne Cole in Sydney and Amruta Khandekar Editing by Gareth Jones and Matthew Lewis)