The currency of east Africa's biggest economy traded at 85.30/40 to the dollar at 0808 GMT, weaker than Monday's close of 85.20/30. The shilling is 0.2 percent weaker against the dollar so far this year.

"We have seen some dollar buying in the market, but today we expect supply (of dollars) from tea sales to support the shilling," said Duncan Kinuthia, head of trading at Commercial Bank of Africa.

Kenya is the world's biggest exporter of black tea and the crop is one of its largest foreign exchange earners, bringing in $1.27 billion last year.

Traders said they expected the shilling to trade in the 85.00-85.50 range this week, supported further by persistent liquidity mop ups by the central bank.

"The central bank's mop ups are also keeping the shilling supported," added Kinuthia.

The regulator continues to soak up liquidity, and its actions have helped the shilling to stabilise against the dollar this year.

The local unit slid sharply in 2011 as inflation soared to a peak of 20 percent and the central bank was accused by market watchers of being too slow to respond.