BOSTON (AP) — President Barack Obama spent his Labor Day courting labor unions.

Obama was met with resounding applause at a major union rally in Boston when he said he’d signed an executive order aboard Air Force One requiring federal contractors to give paid sick leave to their employees.

The Labor Day gesture to workers’ groups comes as Obama works to smooth over tensions with the labor movement over his trade agenda. Major unions are opposing Obama’s push for sweeping new trade deals with Asia and Europe, with some threatening to work against Democrats who voted to support those talks in Congress.

Under the executive order, employees working on federal contracts gain the right to a minimum of one hour of paid leave for every 30 hours they work. Stretched out over 12 months, that’s up to seven days per year.

Business groups have argued that Obama’s order would make it harder for small businesses to retain federal contractors and could hinder economic growth.