The Takeover Panel on Wednesday gave Adecco (NYSE: ADO - News) until the end of next month either to announce a firm intention to bid for Michael Page International or to walk away.

The "put up or shut up" ruling which sets a deadline of September 30 had been accepted by both parties, the Panel said. Michael Page had approached the Panel, which regulates takeovers in the UK, asking for such a ruling after Adecco said last week that it was keeping its options for a bid open.

In midday trading Michael Page shares were down 1¾p at 347½p.

The approach by the Swiss-based group, which is the largest employment company in the world, was worth around 400p a share to Michael Page investors, but their board said that undervalued the recruitment company.

Adecco's interest first became public in early August when Michael Page announced that the two sides were in talks. However, in mid-August Michael Page said it had ended the talks because the indicated offer was too low.

Last week Michael Page announced half year results showing a 22 per cent increase in pre-tax profits to £84.1m.

Adecco had made two proposals: either a 400p a share bid in cash or a deal involving Michael Page issuing new shares to Adecco to give it a 50.1 per cent stake in the group. Michael Page would use the cash received to pay around 200p a share to its investors.

But Michael Page said that idea not only materially undervalued the company but also said the transaction structure was "unattractive for shareholders, as they would become minority shareholders in a company controlled by Adecco."

So far Adecco has been looking for a recommendation from Michael Page for any offer, but it kept open its option to make a hostile bid.

Under the Panel's ruling, if Adecco decides to walk away on September 30, it cannot then bid for six months without going back to the Panel for permission.