Gold climbed back above the $4,600-an-ounce mark as investors viewed the U.S. Treasury's plans to expand bond buybacks to bring long-term yields lower as a sign of stress, sparking a fresh round of dollar selling.

In early U.S. trading, New York futures rose 1.4% to $4,636.30 a troy ounce, on track for a weekly gain of 4.5%. Other precious metals also advanced, with silver gaining 2% to $69.50 an ounce and platinum rising 3.2% to $1,898.80 an ounce.

The latest gains follow a sharp selloff in long-dated U.S. government bonds that pushed yields higher and raised concerns about the outlook for U.S. debt and the dollar. The Treasury said it would at least double its purchases of longer-dated government bonds in an effort to bring down long-term borrowing costs.

The move helped ease pressure on the bond market, with long-term yields moving lower. But it also triggered a new round of dollar selling, as investors questioned whether the Treasury's intervention signaled deeper concerns about the government's borrowing costs and fiscal position. A weaker dollar makes gold more attractive to investors holding other currencies.

"The signal matters: attempts to contain borrowing costs without addressing the underlying fiscal imbalance may fuel concerns about financial repression and currency debasement," said Ole Hansen, head of commodity strategy at Saxo Bank.

The so-called debasement trade--buying assets expected to retain their value against the weakening of the U.S. dollar and other fiat currencies--came under pressure earlier this year as the Iran war pushed energy prices higher, stoking inflation concerns and strengthening the dollar.

"Gold's ability to rally despite historically elevated long-end yields suggests investors are looking beyond the traditional opportunity-cost relationship and focusing instead on the sustainability of government borrowing," Hansen said.

Markets have also scaled back expectations for higher interest rates following recent U.S. economic data. According to CME Group's FedWatch tool, traders are now pricing a 65% probability that the Federal Reserve will leave rates unchanged at its next meeting.

Gold is also benefiting from continued central bank purchases and inflows into exchange-traded funds. Next week, investors will focus on the Personal Consumption Expenditures report, the Fed's preferred measure of inflation, for further clues on the path for interest rates.