More than a dozen east London bus routes are at risk of chaos and cancellation over the Christmas and New Year period - including seven to the Westfield shopping centre in Stratford.
Two 48-hour bus strikes have been called by the Unite union in protest at alleged bullying and “union busting” at Leyton bus garage.
Stagecoach, the parent company of the bus firm involved, says it “utterly refutes” the union’s claims.
The 97 bus, which runs between Chingford and Stratford via Walthamstow and Leyton, is one of at least 13 routes expected to be affected by walkouts by about 350 drivers.
Other routes that will see delays and cancellations will be the 58, 86, 135, 236, 276, 308, 339, 488, D8, W13, W14 and 678.
The 86 links Romford and Stratford, while the 276 also serves Stratford on its way to and from Newham hospital.
The 308 calls at Stratford bus station and Stratford City bus station, on the north-eastern side of Westfield, as does the 339. The D8 serves Stratford, as does the 678.
The 488 serves Homerton hospital. The W14 terminates near Whipps Cross hospital.
The strike will involve two 48-hour walkouts by Unite members who work for the Lea Interchange Bus Company – a subsidiary of Stagecoach - at the Lea Interchange Bus Garage in Leyton.
These are due to take place on December 12 and 13 and January 8 and 9.
Unite said 98 per cent of drivers who took part in a ballot voted to strike.
According to Unite, the dispute centres on allegations of “union busting” and “bullying”.
Stagecoach says it “utterly refutes” the union’s claims.
Unite says its representatives at the depot have been the target of aggressive behaviour since a change in management a few months ago.
The chair of the branch was suspended, dismissed and then reinstated, while another rep has been suspended on “trumped-up charges” following an altercation with management, according to the union.
Unite believes the reps are being targeted for undertaking trade union activities, which goes against employment law.
Unite general secretary Sharon Graham said: "Unite will never stand idly by when an employer uses union busting and bullying tactics.
"Management at the depot must change tack or face disruptive action. Unite members at the Lea Interchange Bus Company have the union's full support."
Unite regional officer John Murphy said: "We understand that those who rely on these bus services will be concerned to hear of industrial action, but this dispute is entirely the fault of the employer for bullying hardworking members of its workforce.
"The ballot result shows the strength of solidarity between bus drivers and their colleagues who have been affected by union busting. Management still have a chance to stop this disruptive action, but it relies on them radically changing their behaviour towards our reps."
A spokesperson for TfL, which contracts Lea Interchange Bus Company to operate the routes, said: “We encourage Unite and Stagecoach to work together to come to an agreement and avoid disruption to Londoners.”
A Stagecoach London spokesperson said: “Our drivers at Lea Interchange Garage who are members of Unite the Union have now voted in favour of taking strike action.
“It would be inappropriate to comment on cases involving any individuals, but we utterly refute the allegations made by Unite of union busting and bullying.
“All employees are held to the same standards of behaviour, regardless of their role, and any allegations of misconduct are handled in line with our established policies and procedures.
“It is disappointing the situation has reached this point, but we value our ongoing relationship with Unite and remain committed to resolving any concerns through the proper channels.
“Our priority continues to be delivering a safe and reliable bus service for our customers, and we will work to minimise any disruption.”
