KYIV, March 12 (Reuters) - Ukraine's 2024 combined grain and oilseeds harvest is likely to shrink to 76.1 million metric tons from 82.6 million tons last year, Ukrainian grain traders union UGA said on Tuesday.

The UGA said the harvest could include 26.3 million tons of corn, 20 million tons of wheat and 13.7 million tons of sunflower seeds.

"The potential decline in harvest in the new season will be caused by a reduction in sown areas, mainly under grain crops, due to unfavourable global pricing conditions and relatively expensive export logistics," UGA said.

The union said the smaller output could cause a decrease in 2024/25 July-June exports to 43.7 million tons from 53.1 million tons expected for the current season.

UGA said the 2024/25 exports might include 20.5 million tons of corn, 13 million tons of wheat, 4 million tons of soy beans, 3.6 million tons of rape seeds and some tonnage of other oilseeds and cereals.

The union said Ukraine harvested 29.6 million tons of corn, 22 million tons of wheat, 5.8 million tons of barley, 14.2 million tons of sunseed, 4.9 million tons of soy beans and 4.3 million tons of rape seeds in 2023.

UGA forecast that Ukraine could export 26 million tons of corn, 16 million tons of wheat, 3.3 million tons of soy beans and 3.6 million tons of rape seeds in 2023/24 season.

The agriculture ministry gave no forecast for the 2024 grain and oilseed harvest or for the 2023/24 exports.

The ministry said on Monday Ukraine's grain exports so far in March had totalled 1.54 million metric tons versus 1.93 million tons in March 1-13 of last year.

The exports in the 2023/24 July-June marketing season have fallen to around 31.2 million tons from 34.2 million a year earlier, the ministry data showed.

Exports so far this month have included 12.5 million tons of wheat, 16.7 million tons of corn and 1.76 million tons of barley.

Ukraine has traditionally exported around 95% of its grain via its deep-water Black Sea ports. (Reporting by Pavel Polityuk; Editing by David Goodman and Jan Harvey)