Facing a shareholders' vote on December 23 after Tata Sons moved a resolution to remove him as an independent director of Tata Chemicals, Wadia also said the series of allegations against him were "totally false and baseless".
"I had raised my serious concerns over the years for providing continuing financial resources of the company towards the overseas business and assets, which were continuously under performing and incurring substantial losses," he wrote in a letter to the shareholders of the company.
However, decision was ultimately taken by consensus, he added.
"Unfortunately shortly after the acquisition the profitability became negative and continued to remain so... This has now led to an impairment on this acquisition of approximately Rs 1,600 crore," Wadia wrote.
More From This Section
The company is currently looking to extricate itself from substantial part of its UK business, including the pension fund issues, which it has inherited from the acquisition.
Highlighting flaws in the inorganic expansion approach of the company, Wadia said: "During the last ten years mainly due to various acquisitions, the consolidated debt of your company went up from Rs 1,827 crore to Rs 8,695 crore, an increase of Rs 6,800 crore."
This included the funding required for other joint ventures and subsidiaries. The total impairment of all the various investments made is approximately Rs 2,000 crore, he added.
Wadia also claimed that the statement issued by the Independent directors of Tata Chemicals on November 10, "affirming confidence in the Board, Chairman and the management in the conduct of the company's business was a unanimous statement".
Taking a dig at the cross holdings of Tata Chemicals in various Tata group listed and unlisted firms, Wadia claimed the approximate value of the unlisted shares is around Rs 7,200 crore or more.
"The current value of the listed shares is in excess of around Rs 1,300 crore making a total of around Rs 8,500 crore. If these holdings were to be disposed off, your company would be debt free. These cross holdings are being maintained in a debt ridden company only to indirectly keep the voting rights and control in Tata Sons," Wadia said.