The new boss of department store chain Debenhams insisted the UK high street was "alive and well" today as he announced plans to modernise a further 25 stores and open nine new outlets over the next four years, including obe in Darlington.

The expansion drive, which will create 4,050 new jobs, builds on the 20 store refurbishments the retailer announced in June.

Chief executive Michael Sharp said the expansion was a strong signal about its commitment to the UK high street, which he said Debenhams was "backing 100%".

The chain, which operates 163 stores in the UK and Ireland, eventually hopes to boost its UK store portfolio to 240. The nine new stores will open between 2012 and 2015 in Darlington, Chesterfield, Burton upon Trent, Carlow and Sligo in Ireland, Bradford, Hereford, Barnsley and Macclesfield.

The expansion update came as the firm said pre-tax profits increased 10% to £166.1m in the 53 weeks to September 3 as it benefited from selling more of its higher margin exclusive ranges.

Debenhams said its number of international franchise stores will double to 130 over the next five years.