Air traffic controllers in Canada are sending hundreds of pizzas to their US counterparts who are working through the federal government shutdown.
A collection started by employees had blossomed into an industry-wide show of solidarity, the Canadian Air Traffic Control Association told the BBC.
The partial government shutdown – now in its 24th day – has become the longest in US history.
It has affected 800,000 public workers and closed many government offices.
Air traffic controllers are among about 450,000 employees who are unable to suspend their work or take up another job, and so continue to work without pay.