After the 10-year yield reached a new decade high on Friday, the Bank of Japan intervened in the Japanese government bond (JGB) market for the sixth time this month, placing the central bank in a conflict with market forces as U.S. rates rose.

After hitting heights the day before, the benchmark JGB yield increased to 0.845% at the start of trade, its highest level since July 2013.

However, it quickly subsided when the BOJ began a fund-supplying operation designed to entice banking institutions to seize low-cost loans to purchase JGBs. The benchmark yield, dropping as low as 0.83%, had returned to 0.835% by 0610 GMT, only 0.5 basis points below Thursday’s closing price.

Under its yield curve control (YCC) policy, the BOJ controls the 10-year yield at 1% after unexpectedly doubling it at the end of July. The central bank has intervened multiple times to slow the rate of hikes, demonstrating that it will not put up with sudden advances toward the ceiling.

According to Shoki Omori, head of the Japan desk at Mizuho Securities, “the BOJ wants market participants to acknowledge that they’re still there with YCC.”

“The message is simple: Don’t sell JGBs too much, and don’t challenge the BOJ.”

Policymakers have recently increased their involvement as Japanese rates buckled under the gravitational pull of U.S. yields. For the first time in more than 16 years, the 10-year Treasury yield momentarily crossed the crucial 5% threshold on Friday.

In its most recent operation, the BOJ offered to provide five-year loans against collateral, using the instrument for the second time this month. It can also acquire more bonds, which it has done three times this month, including this week.

By intervening in the bond market, Japan’s central bank risks tilting the yen to the lower side of 150 per dollar, which many consider the cutoff point for currency intervention.

Since the BOJ’s July 28 policy statement, widening interest rate spreads have caused the yen to fall by as much as 7.1% versus the dollar, as the unrelenting rise in U.S. rates trumped the promise of greater flexibility in YCC operations.

However, after temporarily reaching that level at the beginning of the month and abruptly falling back, the exchange rate has stabilized below 150. Authorities may not have intervened in the currency market, contrary to some speculation, according to data from the BOJ.

A political hotspot, the weak yen raises the cost of imported food and energy at a time when Prime Minister Fumio Kishida could be considering calling an early election.

It would be more challenging for the BOJ to interfere in the JGB market if the yen crossed the 150 barrier. Masayuki Kichikawa, chief macro strategist at Sumitomo Mitsui DS Asset Management, said that due to the yen’s stability, the BOJ can attempt to control long-term interest rates while simultaneously monitoring the response in the foreign exchange market. “That’s the kind of delicate balancing act facing the BOJ.”