Oil prices were little changed on Friday as a strong dollar and concern over the economy of top oil importer China were countered by a tighter supply outlook.

Brent crude prices fell by 9 cents, or 0.1%, to $85.02 a barrel by 1235 GMT. U.S. West Texas Intermediate crude futures slipped 24 cents, or 0.3%, to $82.58.

The U.S. dollar index climbed for a second consecutive session after stronger than expected data on the U.S. labour market and manufacturing earlier in the week. A stronger U.S. currency dampens demand for dollar-denominated oil from buyers holding other currencies.

A lack of concrete stimulus measures from top oil importer China has also weighed on commodities, ANZ analysts wrote.

Meanwhile, Chinese officials acknowledged on Friday that the sweeping list of economic goals re-emphasised at the end of a key Communist Party meeting this week contained "many complex contradictions", pointing to a bumpy road ahead for policy implementation in the world's second-largest economy.

China's economy grew by a slower than expected 4.7% in the second quarter, official data showed, sparking concerns over its demand for oil.

A global tech outage on Friday disrupted operations in multiple industries, with airlines halting flights, some broadcasters going off-air and everything from banking to healthcare hit by system problems.

LSEG Group's data and services were back up and running on Friday after an outage caused some disruption across financial markets earlier in the day. Reuters provides news for LSEG's Workspace platform.

Meanwhile, two large oil tankers were on fire on Friday after colliding in waters near Singapore, the world's biggest refuelling port, with two crew members airlifted to hospital and others rescued from life rafts, authorities and one of the companies said.

Oil prices found some support in the previous two sessions after the U.S. government reported a bigger than expected weekly decline in oil stockpiles.

The OPEC+ producer group, meanwhile, is unlikely to recommend changing its output policy, including a plan to start unwinding one layer of oil supply cuts from October, three sources told Reuters on Thursday.

"We think Q3 balances are set to tighten, due to continued OPEC restraint and seasonal demand increases, before weakening in Q4 on additional supplies from OPEC+ and the U.S.," BNP Paribas analyst Aldo Spanjer wrote in a research note.

(Reporting by Ahmad Ghaddar Additional reporting by Sudarshan Varadhan in Singapore Editing by David Goodman )