A weak global economy will put downward pressure on Britain's high rate of inflation and as a result the sterling will have to remain weak, according the newest policymaker at the Bank of England Ben Broadbent.

Broadbent said Britain's monetary policy framework remained credible, as wage growth was slow and medium-term inflation expectations had not risen.

Broadbent, who joined the Bank's Monetary Policy Committee (MPC) in June, added he was "reasonably close" to voting for increasing the Bank's quantitative easing programme, a move which in itself would lower the value of the pound.

"The international market is clearly disinflationary" said Broadbent, speaking at the Thomson Reuters' London headquarters earlier today.

"Slow growth in the United States, the sovereign debt crisis in the euro zone and its knock-on effects on the cost of finance for UK and European banks - all threaten a further tightening in retail credit and a further slowing in domestic activity," he said.

"These effects are already visible and, over the medium term, look set to dominate any remaining 'pass-through' from sterling's depreciation to domestic inflation."

Inflation picked up to 4.5 percent in August, and has been well above the Bank of England's 2 percent target since the start of 2010

The monetary policy debate has shifted in recent months from interest rates and back to quantitative easing - a term for injecting cash into the economy in order to stimulate growth - from its current level of £200 billion.

Sterling lost around a quarter of its value in 2007 and 2008, and Broadbent said this had been a major cause of past inflation.

Sterling weakness may persist for a lengthy period, as rebalancing of the economy towards exports was likely to be hampered by a "sclerotic" banking system, Broadbent said.

"At least for given trends on the demand side, sterling's real exchange rate will have to remain weak for some time to come," he said.