(Read more: ECB to get drastic? QE could be on the table)
Weidmann said that about two thirds of the falloff in euro zone inflation to 0.7 percent, the lowest since the economy was deep in recession in 2009, could be attributed to falls in energy and food prices.
"Monetary policy should respond to such factors only in the event of second round effects," he told a conference in Berlin, saying he would not talk about current monetary policy ahead of the ECB's monthly policy meeting next Thursday.
"With regard to the rate of inflation at the moment, the euro area is not in a self-enforcing downward spiral of price decreases, which is nominally the definition of deflation," he said.
Consumers not hesitating
He said consumers were not delaying purchases in anticipation of falling prices and the bank expected a recovery to gradually push inflation rates back up.
"This is not to say that a protracted period of lacklustre growth will not be an issue for policymakers," he said, noting that he backed further structural reforms within euro zone states and an unplugging of banks' credit provisioning to the real economy.
But Weidmann warned about the risk of running very low rates for an extended period.
"It is obvious to me that extremely low rates are a risk to financial stability," he said.
(Read more: Spanish CPI shock flags euro deflation risks)
With investors firmly focused on whether the euro zone's central bank will act to bolster a slow economic recovery, Weidmann surprised financial markets last week by saying that negative interest rates were an option to temper euro strength.
He also said then that buying loans and other assets from banks to support the bloc was not out of the question.
Those comments appeared to be a shift in tone from the long-held resistance to quantitative easing of the powerful German central bank.
The Bundesbank has been a stern opponent of the ECB's government bond purchase programs, drawn up during the debt crisis, saying they pushed it too far into the realm of financing governments.