The Prime Minister made the request at a dinner in Florence The previous day, Mr Schroder criticised Vodafone's pounds 77bn bid, echoing the stern resistance from Mannesmann and union leaders to the record-breaking hostile bid .
Mr Schroder said on Friday: "Hostile takeovers destroy a company's culture. They harm the target but also the predator itself in the medium term. I much prefer French-German co-operation because it is amicable."
The comments have angered both political and business leaders as they reinforce the idea that Europe is anti-British.
Chris Gent, chief executive of Vodafone, has been keeping the Prime Minister informed of the progress of the bid. At a breakfast meeting last week, Mr Blair gave Mr Gent his full backing for the bid.
But that has put Britain on a collision course with Germany, which remains reluctant to countenance foreign ownership of domestic companies even though two of Britain's mobile phone companies - Orange and One2One - have succumbed to German bids this year. No German company has ever been taken over as a result of a hostile foreign bid.
Although Vodafone has insisted that no jobs will be lost should its bid succeed, Mr Schroder remains acutely aware of the fears of German unions. Demonstrations against the bid took place in Mannesmann's home town of Dusseldorf on Friday, where 800 workers protested against Vodafone's move. Mannesmann has denied that it is behind the demonstrations, maintaining that its fate should be decided by shareholders.
Calls for the Prime Minister's intervention came as Vodafone stepped up its campaign to convince Mannesmann shareholders to accept its pounds 77bn bid even though the company's board has rejected the deal.
Mr Gent is arguing that Vodafone and Mannesmann represent an ideal strategic fit and would create a company with formidable strength in the mobile phone markets of the UK, Germany, France and Italy. Mr Gent is hopeful of winning the support of the 30 per cent of the company controlled by investors who also own shares in Vodafone.
However, a significant minority of Mannesmann shares are in bearer form, making it very difficult for Vodafone to track down and lobby their owners. Vodafone is planning to press its case with an advertising campaign in the German press, although the notices are expected to be low-key at first.
German institutional invest-ors have reacted cautiously to Vodafone' approach so far. Both Hypovereinsbank of Munich and Frankfurt's Commerzbank have recommended investors decide for themselves. Mannesmann shares fell 7 per cent to 193.1 euros on Friday, indicating growing domestic scepticism over Vodafone's chances.
Matthias Trimm, a fund manager at DWS Investment in Frankfurt, said: "The offer isn't high enough. It will be a challenge for Vodafone to get a majority of shareholders to support this bid." A Mannesmann spokesman said: "We are confident that our defence strategy will be successful."
Mannesmann chairman Klaus Esser has spent the weekend with his advisers to finalise the German group's defence strategy. He will argue that the bid does not adequately reflect the value of Mannesmann, whose shares have rocketed in the last few years thanks to the boom in European telecoms.
Mannesmann has denied that it is seeking a "white knight" .