UPDATE 3-Oil firms as China's slowdown not as steep as some expected

* China posts 6.6 pct 2018 growth, weakest in 28 years

* Weakening China weighs on global economic prospects

* But OPEC-led supply cuts still support crude prices

* U.S. rig count slows, output rises: https://tmsnrt.rs/2NsKwpc (Recasts with higher prices)

SINGAPORE, Jan 21 (Reuters) - Oil prices firmed on Monday after data showed China's economic slowdown was not as big as some analysts had expected, with supply cuts led by the Organization of the Petroleum Exporting Countries also offering support.

International Brent crude oil futures were at $62.83 per barrel at 0259, up 13 cents, or 0.2 percent, from their last close.

U.S. West Texas Intermediate (WTI) crude futures were at $53.92 a barrel, up 12 cents, or 0.2 percent.

Both oil price benchmarks had dipped into the red earlier in the session on fears that China's 2018 economic growth figures would be weaker.

In an expected cooling, China's economy grew by 6.6 percent in 2018, its slowest expansion in 28 years and down from a revised 6.8 percent in 2017, official data showed on Monday. China's September-December 2018 growth was at 6.4 percent, down from 6.5 percent in the previous quarter.

Although the slowdown was in line with expectations and not as sharp as some analysts had expected, the cooling of the world's number two economy casts a shadow over global growth.

"The global outlook remains murky, despite emerging positives from a dovish Fed (now boosting U.S. mortgage applications), faster China easing (China credit growth stabilizing) and a more durable U.S.-China truce," U.S. bank J.P. Morgan said in a note.

Despite this, analysts said supply cuts led by OPEC would likely support crude oil prices.

"Brent can remain above $60 per barrel on OPEC+ compliance, expiry of Iran waivers and slower U.S. output growth," J.P. Morgan said.

It recommended investors should "stay long" crude oil.

Researchers at Bernstein Energy said the supply cuts led by OPEC "will move the market back into supply deficit" for most of 2019 and that "this should allow oil prices to rise to U.S. $70 per barrel before year-end from current levels of U.S.$60 per barrel."

In the United States, energy firms cut 21 oil rigs in the week to Jan. 18, taking the total count down to 852, the lowest since May 2018, energy services firm Baker Hughes said in a weekly report on Friday.

It was biggest decline since February 2016, as drillers reacted to the 40 percent plunge in U.S. crude prices late last year.

However, U.S. crude oil production <C-OUT-T-EIA> still rose by more than 2 million barrels per day (bpd) in 2018, to a record 11.9 million bpd.

With the rig count stalling, last year's growth rate is unlikely to be repeated in 2019, although most analysts expect annual production to average well over 12 million bpd, making the United States the world's biggest oil producer ahead of Russia and Saudi Arabia.

(Reporting by Henning Gloystein; editing by Richard Pullin)