* Revises up profit forecast by 8 percent
* Booked impairment loss on U.S. oil, gas assets
* Sees copper around $5,800 a tonne in Jan-March (Recasts on forecast revision, adds comment)
TOKYO, Feb 6 (Reuters) - Japanese trading house Marubeni Corp on Monday raised its profit and dividend forecasts for the current financial year due to gains from the sale of solar power assets and firmer metals prices.
The revised guidance of 140 billion yen ($1.24 billion) in net profit marked an 8-percent increase from an earlier forecast and was in line with a consensus estimate of 144 billion yen from 9 analysts polled by Thomson Reuters I/B/E/S.
It came despite the company booking an impairment loss of 41.5 billion yen on its U.S. Mexican Gulf oil and gas assets for the October to December quarter, with exploration uncovering less reserves than expected.
Marubeni revised up its annual forecast as it expects to book one-off gains of about 20 billion yen in the January-March quarter from selling some of its solar power assets in Japan, Marubeni CFO Nobuhiro Yabe told a news conference.
Stronger prices for copper and coal are also expected to boost profits, he added.
Marubeni, which owns stakes in copper mines in Chile, is assuming copper prices of $5,800 a tonne for the January-March quarter. London copper stood around that level on Monday.
"We see further upside in copper prices in the mid-term, though gains may not be so big," Yabe said.
Backed by healthy earnings, Marubeni boosted its dividend forecast for the current year to March 31 to 21 yen a share, against an earlier estimate of 19 yen and actual dividend of 21 yen a year earlier. ($1 = 112.5400 yen) (Reporting by Yuka Obayashi; Additional reporting by Aaron Sheldrick; Editing by Joseph Radford)