Corporate America may be due a cut-price mergers and acquisitions spree. US companies, squeezed out of the bidding process during the private equity boom, have headed into this downturn more profitable and with more cash than in previous slumps. However, it is European and Asian companies that are propping-up M&A activity.

With analyst forecasts of the S&P 500 company's future earnings down, it might be a good time for US chief executives to forge foreign empires on the cheap. However, it is European and Asian buyers that have saved investment bankers from being idle. Talks by Korea Development Bank to take a stake in Lehman Brothers is just the latest example of such a deal.

The fall-out from the housing slump has offered foreign buyers a rare opportunity to buy into established US names. Meanwhile, the weak dollar has made it seem as though there is extra value in the US.

Roche in July suggested that the dollar’s perceived low-point against the Swiss franc helped prompt its move on Genentech. Bolstered by the Inbev purchase of Anheuser-Busch, deals involving European buyers have risen by a third since last year.

This has taken up some of the slack on deal volumes that have fallen 20 per cent to $954 billion (£538.9 billion). All-American tie-ups, by contrast, are down about 5 per cent.