Lloyds TSB is reportedly close to announcing the biggest takeover in British banking history. Halifax Bank of Scotland, whose share price plunged by up to 70 per cent this week, earlier said it was in "advanced talks" over a merger with Lloyds that will create a £30 billion banking giant with nearly a third of the UK mortgage market. Both banks declined to comment on reports that a merger deal has been struck. There were immediate fears about the implications for the 135,000 UK staff employed by both firms - 65,000 by HBOS and the remainder at Lloyds TSB. The potential merger is the latest dramatic episode in a week that has already seen the collapse of 158-year-old investment bank Lehman Brothers and the £85 billion (£47.2bn) bail-out of US insurance giant AIG. There were fears for the health of US investment banks Morgan Stanley and Goldman Sachs after shares plunged 25 per cent and 17 per cent respectively on Wall Street. Central banks around the world have pumped tens of billions of pounds into money markets to try to ease nerves. The FTSE 100 index is now at its lowest point since May 2005. The turmoil forced the Bank of England to extend its Special Liquidity Scheme, which allows banks to strengthen their balance sheets by swapping riskier assets for Treasury bonds, until January 30.