Bank of England policymakers were unexpectedly split on new Governor Mark Carney’s long-run commitment to keep interest rates low earlier this month, minutes of their August meeting showed on Wednesday.

Martin Weale, an external member of the Monetary Policy Committee, voted against Carney’s flagship policy fearing it could push up medium-term inflation expectations.

The news is likely to reinforce market doubts that the BoE will keep rates low for the three-year timescale that initially appeared likely when Carney unveiled the guidance last week.

Indicating the scale of division on the MPC, other policymakers said they saw a “compelling” case to restart bond purchases, but were holding off until they could gauge the impact of forward guidance.

Last week the Bank joined a growing bandwagon among central banks to commit to keeping interest rates low for an extended period – in the BoE’s case, until unemployment drops to 7 per cent, subject to several caveats.

One of these was that the central bank would consider raising interest rates if it judged inflation in 18-24 months was likely to reach 2.5 per cent – a timescale that Weale believed was too long.

“(Weale) saw a particularly compelling need to do more to manage the risk that forward guidance could lead to an increase in medium-term inflation expectations, by setting an even shorter time horizon,” the minutes said.

The BoE’s long-term goal remains to return consumer price inflation to 2 per cent, without causing unnecessary volatility in growth. Inflation has exceeded 2 per cent since December 2009, and is currently 2.8 per cent.

However, Weale said he accepted the principles of forward guidance and that he would form his future judgements based on the framework adopted by the majority.

Although several BoE policymakers had expressed sceptic-ism about some forms of guidance on interest rates before Carney’s arrival, most economists had expected Carney to be able to build consensus at the MPC’s August meeting.

Last month Carney succeeded in persuading two MPC members – Paul Fisher and David Miles – to drop their long-standing call for more asset purchases, pending a decision on forward guidance.

But August’s minutes showed that some unnamed policy-makers still thought there was a strong case for more asset purchases, but they would not vote for it until market reaction to forward guidance was clear.

The nine-member MPC voted unanimously to keep the Bank’s main interest rate at 0.5 per cent and total asset purchases at £375 billion.