At the last minute, Londoners were spared the misery of another Underground strike. With its usual callous brinkmanship, the RMT union decided to call off its threatened 72-hour walkout, ostensibly because the pay and conditions package offered by Tube Lines, the company managing three Underground lines, was marginally improved. For many commuters and tourists, the reprieve comes after they had already had to cancel meetings, reschedule visits and alter travel plans. Their anger will hardly be assuaged. It is time for London to put an end to these antics once and for all.

With tedious regularity, the RMT finds a new pretext every few months to indulge in brinkmanship. The overtly political nature of most disputes and the underlying note of class warfare have made it obvious to the three million daily Tube users that obstructive and blinkered trade unionism still flourishes under London's streets.

The ostensible “grievance” of RMT members in this latest dispute was risible. They complained that their pay and conditions package, amounting to almost 5 per cent, was not as generous as that offered to those working for Metronet, the company maintaining the other lines that is now in administration. Three facts alone pointed to the absurdity of their complaint. First, the total amount offered is above inflation and will boost salaries, in some cases, to a figure of £50,000. Secondly, there is no obligation on private companies to offer exactly the same terms as others in the same field. And thirdly, Metronet has collapsed, partly because it mismanaged its finances, whereas Tube Lines is solvent and thriving.

What is abundantly clear is that Bob Crow, the class-obsessed former communist leader of the RMT, has been looking for an excuse to pick a fight with Boris Johnson, the Mayor of London. He knows that Mr Johnson was elected partly because Londoners were tired of disruption on the Underground. He knows also that the mayor wants the unions to sign a no-strike deal. Mr Crow is determined to sabotage any such deal - and provoking a confrontation now was a good way to wrongfoot the mayor.

His timing is astute. Mr Johnson has had a rocky start to his mayoralty, and yesterday suffered the embarrassment of going back on his commitment to hand over the chairmanship of Transport for London to Tim Parker, his transport adviser. Mr Johnson played down opposition accusations that his administration was in disarray, arguing that the job has become very political and that voters would expect him to take responsibility for this important function himself.

Mr Crow may, nevertheless, have overreached himself. To shut down three busy lines at the height of the tourist season would have hardened the determination of most Londoners to confront Mr Crow's opportunism. The strike threat still exists: the RMT membership has not yet voted to accept the improved package.

What he does not seem to realise is the rising anger not only of Tube users but also of the Government, the main parties and trade unions, fear that this throwback to the 1960s could discredit them all. Mr Johnson has sounded emollient this time. He should, however, be preparing for a ruthless confrontation with RMT militants that must end with Mr Crow's defeat.