The east African nation is the world's biggest exporter of black tea, and the crop is the largest foreign exchange earner, bringing in $1.27 billion last year.

Mombasa -based Africa Tea Brokers (ATB) said in a market report that Best Broken Pekoe Ones sold at $4.04-$4.28 per kg, down from $4.00-$4.34 per kg last week.

Best Pekoe Fanning Ones fetched $3.84-$4.32 per kg compared with $3.78-$4.18 per kg at the previous sale.

ATB said 118,635 packages were offered for sale, with 13.37 percent going unsold. Last week, 113,928 packages were offered with 20.1 percent going unsold.

Buyers from Egypt bought more tea than last week, as did those from Afghanistan this week, ATB said.

The industry regulator Tea Board of Kenya has said export earnings were expected to rise 1 percent year-on-year to 110 billion shillings ($1.30 billion) in 2012, despite a forecast drop in production.