Crude oil dipped in Asia early Friday as rebel attacks in Yemen waned and data from Japan painted a mixed picture on demand. 

Earlier on Thursday, officials from the Saudi Arabian government said they launched an operation nicknamed Decisive Storm "in order to defend legitimate government in Yemen and to prevent the Houthi militias from controlling the country by force."

In Japan on Friday, the country reported that February national core CPI (excluding perishables but including energy) rose 2.0%, less than the 2.1% year-on-year gain expected, a 21st year-on-year rise but the smallest gain since 1.3% in March 2014.

The unemployment rate came in at 3.5% as expected, down from 3.6% in January, while the job offers to seekers index met its 1.15 expectation (115 job offers for every 100 people looking for work), up from 1.14 in January and posting the highest reading since 1.19 in March 1992.

Household spending fell 2.9%, less than the 3.2% year-on-year decline seen in real terms, but still an 11th consecutive year-on-year drop.

February preliminary retail sales data showed a drop of 1.8% year-on-year, more than the 1.5% decline expected and the second straight year-on-year drop after a 2.0% decline in January.

On the New York Mercantile Exchange, crude oil for May delivery fell 0.93% to $50.95 a barrel.

Overnight, crude oil futures came off the highest levels of the session on Thursday, as traders continued to monitor the direction of the U.S. dollar to gauge the appeal of dollar-denominated commodities.

Elsewhere, on the ICE Futures Exchange in London, Brent oil for May delivery rallied $1.48, or 2.61%, to trade at $57.96 a barrel on Thursdeay after touching a session high of $59.76, the strongest level since March 9.

The dollar found support after data showed that the number of people filing unemployment assistance in the U.S. last week fell to a five-week low.

The U.S. Department of Labor said earlier that the number of individuals filing for initial jobless benefits declined by 9,000 last week to hit a five-week low of 282,000. Analysts had expected initial jobless claims to fall by 1,000 to 290,000 last week.

Global oil prices spiked more than three dollars during the Asian session on news that Saudi Arabia launched air strikes in Yemen to counter Iran-backed Houthi rebels, fuelling concerns over a disruption to supplies from the oil-rich region.

Oil traders are sensitive to risky geopolitical news involving Saudi Arabia, which has 16% of the world's oil reserves and maintains the world's largest crude oil production capacity.

There are fears that an escalation of hostilities could set off a conflict across the region and send oil prices skyrocketing.

Countries in the Middle East were responsible for nearly 35% of global oil production last year.