The new Mayor is a fact of life. And the RMT is a trade union, not a political party.

Our role is to act in the interests of RMT members, but in doing so we believe we also act broadly in the interests of the travelling public.

The publicly owned, accountable, affordable, integrated and safe transport network we seek in our members' interests is also overwhelmingly desired by the Londoners our members serve.

Rail privatisation and the partprivatisation of Tube infrastructure - the PPP - remain as deeply unpopular among commuters as they are for our members because passengers, like transport workers, have had to live with the consequences.

We oppose privatisation not for ideological reasons but because it is wasteful, inefficient and downright dangerous.

When Metronet went belly-up, taxpayers were left with a £2billion bill and it threatened to derail the upgrade programme that is essential if we are to have a world-class Tube in time for the Olympics. Yet the shareholders walked away to sniff out their next PFI contracts. Last September 2,500 RMT members at Metronet went on strike to prevent any further dangerous fragmentation of the Tube's maintenance workforce, and to prevent the people who keep the network going being made to pay for the shareholders' shameful behaviour.

Metronet's contracts now stand to be re-absorbed into the Tube structure. It is right and proper that the new Mayor allows that process to take its course.

It must surely be unthinkable to repeat the PPP tragedy by reprivatising the Metronet contracts, and Boris Johnson may as well know now that we will resist any attempt to do so, with every means at our disposal.

Our members have never taken strike action at the drop of a hat - the legal constraints we face make that charge laughable.

But it would be insane for us to surrender our democratic right - our human right - to withdraw our labour to defend our interests. Politicians from all sides praised South African dock workers when they refused to handle a Chinese shipment of arms bound for Zimbabwe, but had that happened in Britain the union involved would have been hauled into court.

So, for the new Mayor's benefit, I say this: the RMT wants good industrial relations, but it will never enter into a no-strike agreement.

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