The number of staff being displaced is many times the 200 we were told would be the case during negotiations.

Our members have the legal right to refuse to undertake duties that would put themselves or the travelling public in danger. [We] will give complete support to any driver who refused to move a Northern line train on safety grounds.

Given the urgency of the situation and the fact that it can take up to a month to ballot, we will not be sitting on our hands,

I think it is scandalous what has been put around in the media this weekend about this being a one-off,

No doubt we will once more be accused of disruption but ... the blame once again lies squarely with management trying to impose rather than negotiate.

Once again Tube management have jumped the gun and are trying to impose policies without agreement.