By Kevin Buckland and Samuel Indyk

LONDON (Reuters) – The yen surged to a four-month peak towards the greenback on Tuesday after the Financial institution of Japan surprised markets by deciding to overview its yield curve management coverage and widen the buying and selling band for the 10-year authorities bond yield.

Whereas it stored broad coverage settings unchanged – pinning short-term JGB yields at -0.1% and the 10-year yield round zero – the BOJ determined to let long-term yields to maneuver 50 foundation factors both facet of its 0% goal, wider than the 25 foundation level band beforehand.

The greenback final traded 3.5% weaker at 132.35 yen. It hit a low of 132 yen, a stage final seen in mid-August.

Most BOJ watchers had anticipated no adjustments till the present governor Haruhiko Kuroda’s 10-year time period ends on the finish of March.

“This was actually out of the field,” mentioned Bart Wakabayashi, department supervisor at State Road (NYSE:) in Tokyo.

“We’re seeing them begin to take a look at the market concerning the exit technique,” he added. For dollar-yen, “we may see a break beneath 130. It’s totally a lot inside attain this 12 months.”

The ten-year JGB yield jumped to 0.46% from the earlier cap at 0.25%. It pulled equal U.S. Treasury yields increased as effectively, with the 10-year hovering to the best this month at 3.711%.

The sank, dropping 0.6% to 103.99, inside its buying and selling vary this month of 103.44 to 105.90. The index measures the U.S. foreign money towards the yen and 5 different main friends, together with the euro and sterling.

The index had been transferring in direction of the highest of that vary earlier than the BOJ announcement as traders continued to evaluate the Federal Reserve’s message of upper rates of interest for longer.

The yen’s good points have been broad, with the euro tumbling as a lot as 3.3% to the bottom since late September at 140.17 yen and sterling additionally sliding some 3.4% to the bottom since Oct. 12 at 160.34 yen.

In opposition to the greenback, the euro was up 0.2% at $1.0628 and sterling edged 0.07% increased to $1.2154.

The fell over 3.6% to 88.34 yen, a seven-month trough, and New Zealand’s dipped 3.8% to 83.82 yen, a two-month low, respectively.

On the post-announcement media briefing, Kuroda sought to emphasise that the change was “not an rate of interest hike,” however to enhance bond market perform. He reiterated it was too early to debate an exit from stimulus.

“It is telling that the yen has maintained its energy after the announcement, suggesting the market would not imagine Kuroda,” mentioned Jane Foley, head of FX Technique at Rabobank.

“All of the market sees right here is that the Financial institution of Japan have opened the door a crack in direction of additional coverage tightening and the market appears pretty sure that would come within the spring,” Foley added, saying that dollar-yen may fall as little as 125.