LONDON (ShareCast) - London‘s top stocks fall deeper into the red as credit concerns unnerve market sentiment again.

Northern Rock is expected to receive up to eight proposals today, deadline day, for buying all or some of the stricken bank, but it is whether another lender is in trouble that is taxing investors. Alliance & Leicester, HBOS and Royal Bank of Scotland are all lower again.

British Airways has largely shrugged off reports that it faces a multi-million-pound compensation bill after a deal in which it has agreed to pay some passengers £430 each for cancelling their flights. The Times said the deal opens the way for thousands of passengers — who were left stranded in February because of an industrial dispute — to make claims against the airline.

British Land fell to its lowest in around two years today after Lehman Brothers downgraded the real estate giant to 'equal-weight' from 'overweight' following Thursday’s interim figures.

Lonmin took a step back Friday as Lehman Brothers cut the platinum miner to 'underweight' from 'equal-weight', with price target dropped to 3,100p from 3,400p.

A Citigroup downgrade to 'sell' from 'hold' sent Twinings tea maker Associated British Foods into the red.

Tullow Oil has slipped back having led earlier, though tobacco groups Imperial and BAT are also going well for a second day.

Elsewhere, Aero Inventory has signed a ten year exclusive contract with ACTS Aero Technical Support & Services Inc to supply aircraft parts. The contract commencement date is 15 November 2007. The total consideration to be paid to ACTS amounts to US$95m. The contract is expected to generate revenues for Aero Inventory of some US$1.2bn over the initial ten-year contract period.

Surgical instruments specialist Gyrus has received a writ from ArthroCare alleging an infringement of one of ArthroCare's patents. Gyrus said the action related to a number of its products, including its jPlasmaKnife and Plasma Trissector, but that they formed a very small percentage of overall group revenues.

Engineer 600 Group's interim operating profit before net financial income and tax was £0.6m (2006: loss of £0.5m). European markets, including the UK, experienced significant growth. North America has shown some softness in recent months reflecting current difficulties in financial markets, it said.

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