Nasdaq and the London Stock Exchange are coming to the end of the noisiest vow of silence ever observed. With the US company's deadline of Saturday for the LSE to open talks almost upon them, the air is thick with blast and counter-blast. Yet apart from the formalities, neither side has discussed the offer directly with the other and neither shows any real sign of doing so.

On the face of it, if the LSE lets Nasdaq walk away this weekend without at least having explored a higher offer, Clara Furse and Chris Gibson-Smith, respectively the London exchange's chief executive and chairman, will be open to accusations that they have not examined all the possibilities on shareholders' behalf. Yet think what would happen if the LSE were to place a call to New York in the next 48 hours: news would certainly leak, the market would assume that the game was up, the shares would drop. No wonder LSE shareholders - many of which bought in at prices above the level of the Nasdaq bid - have not been applying public pressure to the LSE board to start negotiating.