Shares in debt-laden telephone giant Deutsche Telekom have jumped by 9% after the firm started to unload a parcel of shares in its internet unit.

The firm said it was aiming to raise up to 732m euros (£467m; $728m) by selling about 120 million shares in T-Online.

The sale, one of the biggest in recent German history, should help chip away at Deutsche Telekom's 64bn-euro debt mountain.

Telekom, which fell dramatically from shareholder favour last year, is making strenuous efforts to turn itself around, and is embarking on a potentially huge programme of sell-offs.

Keeping control

The sale takes Deutsche Telekom's stake in T-Online down to just under three-quarters, building on a 10% share float in April 2000.

But the telecoms firm is determined to retain management control of its internet arm, which it sees as a key part of its integrated strategy.

Further shares may be sold, Deutsche Telekom said, but its stake would not dip below 51%.

At the same time, Deutsche Telekom is aiming to sell its cable TV and real estate assets, and has been rumoured to be interested in disposing of or otherwise radically shaking up its US mobile operations.