The Hazardous Materials Drivers Union said Wednesday its about 750 members - from a total of some 900 in Portugal - will refuse to work overtime or on weekends and public holidays from Sept. 7-22.
The union says truckers work many hours of overtime to keep the country's 3,000 gas stations stocked.
Truckers ended a seven-day walkout on Sunday, after the Portuguese government instituted emergency measures to keep gas pumps from running dry. Talks with employers broke down late Tuesday.
A spate of strikes has tested the country's Socialist government, traditionally sympathetic to trade unions. But with a general election less than two months away, the center-left government is wary of taking sides.
Copyright 2019 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.