The Japanese yen was the focus of attention in Asia on Monday, momentarily falling to a level of 150 per dollar as speculators banking on a further increase in dollar rates lost out to those anticipating market intervention by the Japanese government.

Israeli airstrikes in Gaza early on Monday put markets on edge as the United States sent more military resources to the area, raising the possibility that Israel’s fight with the Islamist organization Hamas will spread to other parts of the region.

Investors were cautious as they awaited a meeting of the European Central Bank and the release of U.S. GDP statistics later in the week. Ten-year rates were about 4.98% after briefly rising above 5% last week after Jerome Powell, the chairman of the Federal Reserve, said that the U.S. economy’s strength and its hot labor markets would call for tighter financial conditions.

The euro fell by 0.2% to $1.0574, while the dollar index rose by 0.1% to 106.28. After temporarily weakening early on Monday to a level last seen on October 3, when traders believed the Bank of Japan (BOJ) intervened to push it to the higher side of 150, the Japanese yen last traded at 149.93 per dollar.

Masafumi Yamamoto, chief currency strategist at Mizuho Securities in Tokyo, observed that although some investors were wagering that the BOJ would maintain the 150 level, others continued to drive the dollar higher due to rising U.S. rates.

“Potentially there are two camps out fighting around 150, so that’s why dollar-yen doesn’t move from here,” Yamamoto stated.

The BOJ had also demonstrated it will not allow domestic rates to increase much, he added, despite some speculation that the BOJ could make another adjustment to its yield-curve policy range during a planned policy review next week. The benchmark JGB yield reached its highest point since July 2013 at 0.855%. After the BOJ offered further loans to encourage financial institutions to purchase JGBs, yields fell on Friday.

Even though the dollar hasn’t risen in lockstep with yields, the long end of the U.S. Treasury curve has been steadily climbing thanks to expanding term premiums on predictions of faster growth and fiscal slippage.

The trade-weighted dollar index has increased 6.7% since mid-July but has remained essentially constant this month.

“It is a bit of a puzzle that DXY hasn’t retested the early October lows, given its strong foundations of high yields backed by strong growth and strong energy production as concerns grow over the Middle East and haven status,” said Sean Callow, a currency analyst at Westpac.

“However, DXY downside is likely limited to the mid-105s, and we continue to target 109 in Q4/Q1.”

Other observers cited the yen’s and China’s yuan’s stability—both significant elements of the DXY trade index—as the cause of the dollar index’s lackluster movements.

Due to diplomatic efforts over the weekend to keep the situation under control and allay fears of a significant interruption to oil supply, oil prices fell by more than $1 on Monday. Despite a drop in price to $91.14 a barrel, Brent oil futures are still up roughly 10% over the past ten days.

A Reuters poll indicates that while the ECB is done hiking interest rates, it won’t start lowering them until at least July 2024. The ECB meets on Thursday. In September, it increased its benchmark interest rates by 25 basis points.