The Speaker’s office did not provide a comment on the motion.
Mr Blunt acknowledged there was “much to admire” about Mr Bercow’s near ten-year tenure but “enough was enough” as many MPs had “an unshakeable conviction in his bias on the Brexit issue”.
“Even his most partisan supporters for the positive changes he has delivered as Speaker do not now seriously dispute his bias in the conduct of our affairs,” he said.
“If colleagues are too cowed or too content with the direction of his bias to state their view on Speaker Bercow’s obvious partiality then not only will he feel able to continue… but also exercising the power of his office wholly inappropriately.
“The essential attribute of his office is now missing. It should not be allowed to continue, not least without anything being formally said.”
Mr Blunt has said he intends to write to MPs seeking their support for an Early Day Motion (EDM) expressing no confidence in the Speaker.
The EDM is expected to be tabled on Tuesday when the House of Commons returns from recess – however there is no guarantee that such a motion would be debated.