LONDON (Bloomberg) — Bermuda-based Frontline Ltd., the world's largest operator of supertankers, may say first-quarter profit fell 78 percent as oil producers curbed output to bolster prices.

Frontline will probably say net income dropped to $48.9 million, or 63 cents a share, from $221 million, or $2.95, a year ago, according to the median estimate of eight analysts surveyed by Bloomberg News.

The Organisation of Petroleum Exporting Countries cut production three times since September. The group's members in the Middle East lowered their combined production by as much as 16 percent compared with August last year, according to estimates compiled by Bloomberg.

The benchmark rental rate for supertankers, based on Saudi Arabian shipments to Japan, averaged 47.29 Worldscale points in the first quarter, the lowest since the third quarter of 2002. Worldscale points are a percentage of a nominal rate, or flat rate, for more than 320,000 specific routes.

Frontline will report first-quarter earnings today at about 8 a.m. Oslo time. It will hold an investor presentation at 8.30 a.m. and a conference call at 3 p.m.