US Crude Resumes Fall As Investors Seek Safe Havens

NEW YORK, July 7 (Reuters) - U.S. crude oil prices fell for a second straight day on Tuesday as worries about Greece and China's stock market losses sparked an investor flight to safe havens, and technical selling threatened to push oil further into a bear market.

Also weighing on crude prices was Iran's determination to seal a nuclear deal with global powers to bring more supply to the market and the restart of a key oil terminal in Libya.

U.S. crude has lost more than 8 percent since Thursday's close for the sharpest two-day fall since end-November. It settled down 20 cents on Tuesday at $51.98 per barrel.

Brent, the more globally-used crude benchmark, settled up 31 cents at $56.85.

Investors will be looking out for Wednesday's crude stockpiles data from the U.S. government to decide on direction ahead. Analysts polled by Reuters on Tuesday said they expected U.S. crude stocks to have fallen by 700,000 barrels on the average last week. Industry group American Petroleum Institute will issue its own estimates on this at 4:30 p.m. EST (2030 GMT).

"There has been a lot of money looking to pile into the short-side, and there have been an accumulation of different triggers to cue that over a short time," said Paul Horsnell, head of commodities research at Standard Chartered in London.

"None of those work in isolation, but put them all together in a short period and they'll do it. And after that, the technicals kick in to give a further push down."