Boris Johnson's tensions with the Treasury over Crossrail highlight both the threats to London's transport upgrades during the present round of cuts and his own difficult relationship with his party's leadership. Today the Mayor has denied reports that he threatened to resign if London did not get Crossrail: he says he will “almost certainly” stand again in 2012. Neverthless, that denial is unlikely to be of much comfort to the Prime Minister.

The Mayor has previously defended the Crossrail settlement robustly. The Heathrow-Stratford rail link is vital to London's future economic growth. Yet despite committing to the project in principle, both the Prime Minister and the Chancellor have stopped short of guaranteeing funding for it. Yet to force Crossrail to scale back its reach or number of stations now would be very short-sighted. We hope Mr Johnson takes a similarly firm line in defending the budget for vital Tube upgrades.

The danger for David Cameron is two-fold. If the Treasury imposes swingeing cuts on London, it would almost certainly help Ken Livingstone, Mr Johnson's likely opponent in 2012. Today Mr Livingstone launched his transport plan for London, attacking possible cuts and Mr Johnson's planned fare rises in characteristically uncompromising style. Losing London to Labour would be an unwelcome mid-term blow for the Tories.

Yet so would Mr Johnson's early departure from City Hall: he has made little secret of his long-term ambition of returning to national politics. He has a competitive relationship with Mr Cameron. But however much trouble he makes over issues such as Crossrail, in the end it suits Mr Cameron's — and George Osborne's — purposes better to have him isolated in City Hall than building up his leadership ambitions in Parliament. London, for its part, can at least be glad that its Mayor has the power to sway the Government's most senior figures.

Cricket's darkest hour

The crisis engulfing cricket in the wake of corruption allegations against members of the Pakistan team will have many victims. Police and the cricket authorities are now investigating the affair, while it has been suggested that the cricketers in question are unlikely to play for the rest of their tour. But the game, so much a part of the national identity of both nations, will inevitably still suffer.

For the English and county cricketers playing Pakistan over the coming weeks, there will inevitably be doubts about incidents in the games: was a particular no-ball or dropped catch fixed? It risks ruining what should be a thrilling sporting contest. For the remaining Pakistani players, it means their every move will be under suspicion. As for the spectators, who have paid high prices for the international matches, they may wonder if there is any point turning up for such a tainted contest.

There have long been rumours of corruption in the game, especially in Pakistan. The International Cricket Council must sort out this mess and fast if the game's image is not to be irreparably tarnished.

A gift of life

JK Rowling's gift of £10 million to combat multiple sclerosis should be an object lesson in philanthropy for large companies. The author wrote the first sentence of the Harry Potter books, stories with loss and orphanhood at their core, as her mother lay dying from MS. Her donation is a fitting gesture of hope in the face of such suffering. Ms Rowling may be one of the country's richest women but many in the City could learn from her generous example.

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