Yields on U.S. Treasurys fell and the dollar held close to an 11-week low in early European trade after the government said it would spend more on buying back longer-dated bonds.

After 30-year Treasury yields jumped to multiyear highs earlier this week, investors are reading the unexpected intervention as an effort to ease investor concern by signaling the Treasury's willingness to support under-fire debt.

The buyback buoyed global market sentiment more broadly, with U.S. stock futures mostly pointing higher Thursday after making modest gains in the last session.

Meanwhile, Brent crude oil climbed above $93 a barrel after President Trump said he would unleash "ECONOMIC D-DAY" on Iran, including taking action against all businesses linked to the Iranian economy.

Equity investors will look to earnings from U.S. retail giant Walmart.

--Oil prices extended gains for a fifth consecutive day after President Trump said he would launch a major economic campaign against Iran, signaling further escalation and little hopes for an imminent deal. In early European trading, Brent crude was up 1.6% to $93.08 a barrel, while WTI futures rose 1.5% to $85.67 a barrel. "The U.S. has no talks planned with Iran, while the Strait of Hormuz situation remains tense, with limited traffic and ongoing disagreement around reopening conditions," analysts at Sucden Financial said. "This keeps an energy-risk premium in the market and limits how far investors can price out inflation risk, even as today's Treasury announcement gives risk assets some breathing space."

--In the U.S., futures for the Dow Jones Industrial Average slipped 0.1%, while S&P 500 futures added 0.1%. Futures for the Nasdaq were more positive, rising 0.35%. Moderna shares pulled back slightly in after-hours trade after its historic surge Wednesday, falling 9% after more than doubling its market value in the last session following a oncology trial breakthrough.

--Asian equities mostly rose. South Korea's Kospi jumped 5.9%, Japan's Nikkei Stock Average gained 1.4% and Hong Kong's Hang Seng Index climbed 1.05%. Investors watch for an earnings report from Chinese technology giant Alibaba Group Holding ahead of the U.S. market open.

--European stock indexes were mixed at the open, as markets continue to move sideways in muted trade. Autos were the leading sector as the Europe-wide Stoxx 600 was flat. London's FTSE 100 dropped 0.2%, dragged by a 10% fall for JD Sports after the fashion retailer cut its guidance. Metals miners in the index also pulled back. Germany's DAX lost 0.3% as software giant SAP fell 1.8%, though BMW and Continental gained. Autos also rose in Paris, where the CAC 40 was flat as Stellantis and Renault gained 1.8% and 1.4%, respectively. Ferrari rose 1% as Italy's FTSE MIB gained 0.4%, while Spain's IBEX 35 was up 0.35%. The Dutch AEX was flat. Semiconductor stocks edged higher, though Aegon lost 2.9%.

--The dollar traded steady but remains close to the 11-week low reached Wednesday. The increased issuance of short-end Treasurys to finance the U.S. government's expanded buybacks ties the government's financing costs more closely to the Federal Reserve's monetary policy, Danske Bank's Filip Andersson said in an note. Renewed concerns over the Fed's independence may have weakened the dollar in response to the Treasury's announcement, he says. The DXY dollar index traded flat, having reached as low as 98.767 Wednesday.

--U.S. Treasury yields edged lower in Asian trade, extending Wednesday's falls in long-end yields after the Treasury's buyback announcement. "Whatever the reason, clearly the [recent] weakness brought about a response from the U.S. Treasury," Natixis U.S. rates strategist John Briggs said in a note. The fact that the announcement was "very unexpected" sends a strong signal, Briggs said. The 10-year Treasury yield fell 0.8 basis point to 4.644%, while the 30-year yield was down 0.6 basis point at 5.188%.

--Eurozone government bond yields edged lower. "Bunds continue to show signs of stabilization after bullish buyback headlines from the U.S. Treasury," Commerzbank's Erik Liem said in a note. Bond supply will come from France, which will conduct two auctions, the first for short- and medium-term nominal bonds and the second for inflation-linked bonds. The 10-year Bund yield fell 1 basis point to 3.251%.

--Bitcoin stayed elevated after reaching an 11-week high overnight after President Trump urged Congress to pass a crypto regulation bill and the U.S. Treasury announced increased buybacks of long-term bonds. Trump asked lawmakers to pass a "fair version of the Clarity Act" which has stalled in the Senate. Bitcoin rose 1.1% to $69,831 after reaching as high as $69,994 overnight.

--Gold prices held above $4,500 after Wednesday's rally and the release of the Federal Reserve's minutes. In early European trading, New York gold futures rise 0.1% to $4,547.90 a troy ounce. Prices climbed in the previous session on a weaker U.S. dollar and lower U.S. government bond yields after the Treasury said it would at least double the amount of bonds it buys back.