Speaking publicly on Monday afternoon for the first time since a television station announced on St Stephen's Day that he had been diagnosed with pancreatic cancer, Lenihan said he would be the first to admit if he was no longer fit to continue in office.
In a lengthy media briefing at Leinster House, Lenihan said his condition was acute, not chronic, and that he was satisfied he could perform his essential Cabinet functions.
He said he accepted that the state of health of the finance minister was a matter of public interest, but questioned whether there was any real public interest in breaking the news the day after Christmas.
"I'm undergoing treatment as an outpatient, not as an inpatient, so I will be available to deal with matters as they arise and that's the position," he said.
He admitted he had asked doctors if stress might have contributed to his illness but said he had "enjoyed" his time at the Department of Finance and had never "felt under particular stress."
He dismissed any suggestion that he would call in a deputy to help him during his illness.
"There isn't much point having a minister for finance and having a substitute minister for finance and many ministers have offered to assist and I'll consider their offers. But the key issue is that there are some important matters that have to be attended to in the department in the next few months," he said.
"We have the Finance Bill to finalize. Clearly I'll be making the decisions on that in the next few weeks and introducing the bill in the houses (D
