TOKYO, Oct 7 (Reuters) - The yield on Japan's 30-year

government bond rose to an all-time high on Tuesday, extending

its climb from the previous session after the ruling party chose

fiscal dove Sanae Takaichi as its leader, setting her up to

become the country's next premier.

Ten-year JGB yields also marked fresh 17-year peaks, with

the bond market under additional pressure following an advance

for Treasury yields overnight as the U.S. government shutdown

dragged on. Bond yields rise when prices fall.

Investors were also cautious with the Japanese finance

ministry auctioning about 700 billion yen of 30-year JGBs later

in the day.

Weak demand at long-term debt auctions earlier this year

spooked the market, causing a spike in yields and prompting the

ministry to curtail issuance of 20-, 30-, and 40-year

securities.

The 30-year yield rose 2.5 basis points (bps)

to an unprecedented 3.31%.

The 10-year yield advanced 2 bps to 1.69%,

the highest since July 2008.

Other tenors had not yet traded, as of 0037 GMT.

Benchmark 10-year JGB futures sank 0.15 yen to

135.75 yen.

(Reporting by Kevin Buckland; Editing by Subhranshu Sahu)