Government and transports services, including flights, came to a standstill in Tunisia on Thursday amid a nationwide strike by the country’s main trade union confederation which piled pressure on President Kais Saeid, who is already facing a string of crises. The powerful UGTT union called on up to three million public sector workers to strike on Wednesday, halting work at 159 state agencies and public companies to demand concessions on salaries and threatened reforms. The action appeared to be widely observed in the capital Tunis, where post offices and public utilities were closed. The strik…