Industry officials said plantations company revenues were affected by the production disruption caused by last year's wage hike and a drought that followed soon after.
Although rubber prices remain high and most companies are also fetching good prices for tea, another wage hike so soon after giving one would squeeze margins in the industry.
"Although tea and rubber prices are attractive, these sorts of continuous wage increases would definitely put pressure on most plantations companies, especially those suffering from low margins," said Geeth Balasuriya, research analyst at HNB Stockbrokers.
The powerful Ceylon Workers Congress (CWC) labour union, which is represented in parliament, along with other big unions, are threatening to withdraw from a wage deal they clinched only last December.
Labour unions say they are