"But we looked each application without involving politics. There was not patronage. If we did we would be in trouble. That is always a challenge. That is normal, we cannot blame them also.
"We were in that stand throughout. If we played politics we would be in difficulties."
In the 1990s state banks had been bailed out twice at the expense of citizens.
Wickramasinghe said the bank is expected to post a profit of 20 billion rupees this year of which a third would be retained and the rest would be paid as taxes and dividends to the Treasury.
Bank of Ceylon is Sri Lanka's largest commercial bank and key financier of the state.
He said he had given his resignation to President Mahinda Rajapaksa in August but had stayed on until a replacement had been found. His only request was not to appoint a politician as chairman of the bank.From 2007 to 2012 the bank's share of sector assets had grown from 21 to 25 percent and its assets had hit a trillion rupees. In the same period, profits had grown seven fold, assets, loans and deposits had tripled.
Wickramasinghe said he was sad to leave the bank but it had achieved a target of 'One10Twelve' of making ten billion rupees in profits a year and reaching a trillion rupees in assets by 2012.
Wickramasinghe said he was leaving mainly because he felt that major challenges target had been met. To grow at the same pace more capital was needed to leverage.
He said a proposal with several options to raise capital to maintain high growth had been submitted to the finance ministry but there was not response yet.
Wickramasinghe said the bank had an excellent corporate management team and it could sail along with internal capital generation, but that was not challenging enough for him.
He denied the existence of any political differences or disappointment with the administration.
"There is nothing like that at all," he said. "I never did any politics in the bank. I had earlier been at the SEC (securities regulator) and IBSL (insurance board). I had served the government for 8 and a half years but I had never done any politics."
Wickramasinghe had not taken any payment for being chairman, a bank official said.
Responding to queries whether he was resigning due to a disagreement with President Rajapska's son Namal, Wickramasinghe said that was not the reason for his resignation. A question had been asked and an answer given to a young parliamentarian he said.