Delhi Metro Rail Corporation chief E Sreedharan, in an exclusive interview to NDTV, has said that he had to take the responsibility for the bridge mishap in south Delhi.

Sreedharan also said that he had some suspicion about the pillars.

"I had some suspicion about the pillars. Cracks on the pillar had been detected and I had called the design consultant," said Sreedharan.

The Delhi Metro chief said that the consultant had told him that it was merely a hairline crack.

"The problem is with the design or materials. Another designer from Mumbai has been called in," he said.

Talking about his resignation, which was turned down by Delhi Chief Minister Sheila Dikshit, Sreedharan said that DMRC won't be able to meet the deadline if he goes now.

He further said that he would resign after completing phase 2 and would lead a spiritual life.

"I have a successor in mind and the government knows about it," said Sreedharan.

Sreedharan said that the incident has changed him and he is much tougher now.

Referring to the talks of compromise on security to meet deadlines, the Metro chief said that the pace is not too fast and is five to six months ahead of schedule, adding that security is always a priority.

"The safety record of Delhi Metro is comparable with the best in the world," said Sreedharan.

He further said that the risk in underground construction is much more than overground.