The US Treasury has moved to support the long end of the government bond market by doubling the size of planned buybacks of longer-dated debt, seeking to ease liquidity pressures after a sharp selloff pushed the 30-year Treasury yield to its highest level since 2007, Reuters reported. Treasury will increase buybacks of 10- to 30-year Treasury securities to at least $4 billion per operation, from the previously planned $2 billion.

The larger purchases will apply to the 10- to 20-year and 20- to 30-year sectors and will run from September 9 through November 4. S.

fiscal outlook. 184% following the Treasury announcement.

The Treasury said the increase in buyback sizes was aimed at providing greater liquidity to longer-dated nominal securities, where it has seen strong demand from market participants. The department has conducted scheduled purchases of older Treasury securities over the past two years to improve liquidity in less actively traded, or off-the-run, securities, Reuters reported.

Focus on rising borrowing costsThe surge in Treasury yields has raised concerns across financial markets because higher government borrowing costs can also lift financing costs for households and companies. Mortgage rates and other forms of credit can remain elevated when longer-term Treasury yields rise sharply, while the federal government's interest expense also increases.

S. public debt outstanding crossed the $40 trillion mark on Wednesday, underscoring the sensitivity of markets to rising yields and the government's growing financing requirements.

The Treasury's action is intended to provide additional support to the long-duration bond market, although it does not alter the underlying fiscal deficit or the amount of debt the government needs to finance. Market participants also noted that increased purchases of longer-dated bonds could potentially be accompanied by greater issuance of shorter-term debt, including Treasury bills and securities in the fiveto 10-year maturity range.

Limited impact on overall debtDespite the increase in buyback sizes, the programme remains small relative to the size of the overall Treasury market. 5 trillion as of July 31.

The Treasury had said earlier this month that it planned to repurchase up to $69 billion of Treasury securities across maturities between August 6 and November 5. The latest increase in buyback sizes could raise the maximum amount of planned repurchases to about $83 billion.