Distribution drivers in Livingston have voted to strike over plans to re-draw terms and conditions when Tesco relocates its depot just 500 yards.
Tesco has a distribution depot based in Livingston
The Transport and General Workers Union confirmed the ballot result but said no dates for action have been set while talks with the supermarket continue.
In a high turnout ballot, where over 92% of the drivers took part, there was 95.5% in favour of strike.
On taking industrial action short of a full strike, 94.7% were in favour.
Talks between Tesco and the T&G started on Monday and will continue into next week.
Tony Trench, T&G regional industrial organiser and spokesman for the drivers, said the result was a "robust mandate".
"This vote shows how strongly drivers feel about the situation," he said.
The T&G drivers recently received backing from the Scottish TUC.
The full ballot result was 126 in favour of strike action with 6 against and 125 in favour of action short of a strike with 7 against in a ballot of 143 T&G members.
The total number employed in transport at the Livingston site is over 200 but the dispute affects the drivers only.