TOKYO: The 10-year Japanese government bond yield rose to the central bank’s policy ceiling on Monday and superlong yields hit seven-year highs, amid political turmoil in Britain and increased bets for aggressive US rate hikes.

The 10-year JGB yield edged up half a basis point to 0.25%, reaching the top end of the trading band under the Bank of Japan’s yield curve control policy for the first time since Sept. 27.

The 20-year yield added 4.5 basis points to reach 1.110%, a level not seen since October 2015.

Japan’s 30-year yield climbed as much as 5.5 basis points to 1.515%, the highest since June 2015.

Benchmark 10-year JGB futures ended the session down 0.13 point at 148.20, and earlier dropped as low as 148.16 for the first time since Sept. 29.

“The turmoil in the UK is weighing heavily,” said Naka Matsuzawa, chief strategist at Nomura Securities in Tokyo.

“The market is still waiting for answers from the government or the Bank of England to stabilize the market, and until we see that, the superlong zone is going to be the most fragile sector.”

Long-term JGB yields rise, shorter-term notes stay stable

British lawmakers will try to oust Prime Minister Liz Truss this week, the Daily Mail reported. Truss fired Kwasi Kwarteng as finance minister on Friday amid ongoing market gyrations following the new government’s controversial tax-slashing mini-budget.

Yields were also under pressure to rise as the implications for Federal Reserve’s policy from red-hot consumer price data last week continued to reverberate through markets.

Five-year JGB yields rose 1 basis point to 0.090%, matching the high on Sept. 28 and bringing yields to the cusp of a seven-year high.

Two-year JGBs had yet to trade, and last yielded -0.055%.