Tecity, through its investment vehicle Cairns Pte Ltd, raised its offer to $6.50 per share from $5.70, previously, valuing Straits Trading at $2.1 billion.

The new offer is a 12.8 per cent increase over the counter bid from Knowledge Two Investment, controlled by the sons of the late Lee Kong Chian, founder of Oversea-Chinese Banking Corp (OCBC). Knowledge Two offered $5.76 for each Straits Trading share it does not own.

Tecity is owned by members of the family, many of whom are also significant shareholders of OCBC, of the late Tan Chin Tuan, who was credited with building OCBC into a major financial group in Singapore. Mr Tan led the bank from 1966 to 1968.

Knowledge Two, which has control of 32.37 per cent of Straits Trading shares, declined to say if they would revise their bid.

'We believe that our offer presents a unique exit and liquidity opportunity for all minority shareholders of Straits Trading,' director of Cairns, Chew Gek Khim, said in a statement.

The companies in the Tecity group have been shareholders of Straits Trading since the 1950s.

The group owns 22.4 per cent of Straits Trading which focuses on mining, smelting and metals trading, as well as investing in the hotel and property sectors. -- REUTERS