I found the phrase 'concessionary tone' in today's New York Times:
Bloomberg Is Criticized on Storm Response as He Tours City Beyond Manhattan
The mayor on Thursday delivered the message that every street had been plowed, but his concessionary tone was met with frustration in the boroughs beyond Manhattan.
What does 'concessionary' mean in this particular context? None of the translations in my English-Japanese dictionaries seem to fit the case. Can somebody give an appropriate interpretation?