An editorialized image of a falling graph in opposition to the Eastern flag.Natanael Ginting | Istock | Getty ImagesJapan’s central financial institution is anticipated to go out its damaging rate of interest regime this spring, even though slow enlargement will restrict its talent to relieve depreciation power at the yen, consistent with a former Financial institution of Japan board member.BOJ Governor Kazuo Ueda is beneath power to stem yen depreciation pushed by means of the divergence between prime U.S. rates of interest and Japan’s extremely simple coverage. But, he’s additionally constricted by means of prime inflation that BOJ policymakers nonetheless deem unsustainable, even because it crimped home call for and tipped the economic system right into a technical recession. That wonder contraction supposed Japan’s economic system is now the sector’s fourth biggest, falling at the back of Germany.”It is a critical problem and predicament,” Sayuri Shirai, an economics professor at Keio College in Tokyo, informed CNBC’s “Squawk Field Asia” on Thursday. She in the past served as a member of BOJ coverage board from 2011 to 2016, serving to to make financial coverage selections.”Alternatively, I believe BOJ is more likely to take some coverage trade, together with [the] elimination of damaging rates of interest this spring, as a result of I believe they fear about uncomfortable side effects,” she mentioned.The yen retreated to round 150 to the buck this week after U.S. inflation knowledge got here in upper than anticipated, dousing hopes of a faster Federal Reserve charge lower. The yen’s continual weak spot has decreased now not best the buying energy of shoppers in Japan, but additionally the price of the rustic’s exports.”I believe they need to take this chance to perform a little changes, and in addition extra marketplace contributors await that BOJ will perform a little normalization this spring. So without reference to whether or not BOJ is in a position to succeed in 2% in solid approach, I believe BOJ will take some coverage trade this spring,” Shirai added.Even supposing BOJ policymakers deem inflation continues to be now not sustainably pushed by means of home call for, the extended prime inflation charges have hit home intake — a key reason why riding the second one consecutive contraction in Japan’s GDP within the fourth quarter.Whilst inflation has been regularly slowing, “core core inflation” — which excludes meals and effort costs — has exceeded the BOJ’s 2% goal for greater than a 12 months.At its January assembly, the BOJ determined unanimously to stay temporary rates of interest at -0.1%. It additionally caught to its yield curve keep watch over coverage, which assists in keeping the higher restrict for 10-year Eastern executive bond yield at 1% as a reference.BOJ policymakers had been wary and fastidious with their number one process: reflating an economic system that is been mired in a long time of deflationary pressures.Many available in the market be expecting the BOJ to transport clear of its damaging charges regime at its April coverage assembly, as soon as the once a year spring salary negotiations ascertain a development of significant salary will increase. The central financial institution believes salary increments would translate right into a extra significant spiral, encouraging customers to spend.However former BOJ coverage board member Shirai mentioned recently Eastern yen-denominated wages and family intake are each losing.”And so, there’s no signal to peer this about your cycle between worth and wages and [consumer] call for. So on this sense, It is fairly tough for BOJ to take [the path of] normalization, despite the fact that inflation can also be above 2% for a while,” she added.”However on the identical time, this pastime [rate] differential growing large depreciation [pressure for the Japanese yen] … so you spot it is very tough to boost rates of interest.” Shirai mentioned.”So despite the fact that Financial institution of Japan raises rates of interest a bit bit, BOJ has to mention they can not do … steady rate of interest hikes since the economic system is vulnerable. In the event that they perform a little normalization, [it would be] simply [the] elimination of damaging rates of interest — then it does not truly have a lot affect at the depreciation of the yen.”— CNBC’s Lee Ying Shan contributed to this tale.