If inflation turns out to be more persistent than forecast, then past interest rate hikes may have less effect than expected, Lombardelli said in a questionnaire published before a hearing at parliament's Treasury Committee on Tuesday.
She also said there was uncertainty about how much monetary tightening undertaken by the BoE has fed through to the economy, which could leave policy becoming increasingly restrictive.
"Navigating policy through this uncertainty is the key challenge for bringing inflation back to target sustainably and for growth in the near term," Lombardelli, who is currently chief economist of the Organisation for Economic Co-operation and Development, said in the questionnaire.
(Writing by Andy Bruce; Editing by William Schomberg)
