British Airways cabin crews will go on strike for 20 days between May 18 and June 9, the union that represents them said Monday.

“Crew are to take strike action on the following days: May 18-22 inclusive, May 24-28 inclusive, May 30-June 3 inclusive and June 5-9 inclusive,” the Unite union said.

The rolling strikes end just days before the World Cup soccer tournament — one of the biggest sporting events on the planet — opens in South Africa on June 11.

The union’s joint heads, Derek Simpson and Tony Woodley, blamed the airline, saying its rejection of an offer over the weekend left cabin crew with no choice but to strike.

BA responded that it was “saddened but not surprised” by the strike, and said the action has “no semblance of justification.”

(Source: CNN)