Treasurys rose, pushing the 30-year bond yield to a 15-month low, as rising tension in Ukraine and speculation the European Central Bank will buy bonds overshadowed data showing the U.S. economy strengthened.

A gauge of government bonds around the world approached a record high on speculation the ECB is preparing further action to spur a slumping economy. Ukraine said actions by Russia amount to an invasion. Treasurys rallied even as data showed the U.S. economy grew more than initially estimated in the second quarter. The U.S. sold $29 billion of seven-year notes at the lowest yield since May.

“The geopolitical concerns are overriding any kind of economic data,” said Thomas di Galoma, head of fixed-income rates at ED&F Man Capital Markets in New York. “It doesn’t look like it’s going to stop.”

U.S. 30-year yields dropped three basis points, or 0.03 percentage point, to 3.07 percent at 1:06 p.m. New York time, Bloomberg Bond Trader data showed. It reached 3.06 percent, the lowest level since May 2013. The price of the 3.125 percent securities maturing in August 2044 rose 18/32, or $5.63 per $1,000 face amount, to 101.

The benchmark 10-year note yield fell two basis points to 2.34 percent and reached 2.32 percent. It touched 2.30 percent on Aug. 15, the least since June 2013, falling from 3.03 percent at the end of 2013.

The yield on the current seven-year note decreased one basis point to 2.03 percent and touched 2.00 percent, the lowest since Aug. 19.

Note Auction

The U.S. seven-year notes sold today yielded 2.045 percent, matching the average forecast in a survey by Bloomberg News of six of the Federal Reserve’s 22 primary dealers, which are obligated to bid in U.S. debt sales. The yield at the last offering of the maturity on July 30 was 2.250 percent.

The auction’s bid-to-cover ratio, which gauges demand by comparing the amount bid with the amount offered, was 2.57, matching the average at the past 10 auctions.

Bank of America Merrill Lynch’s Global Broad Market Sovereign Plus Index rose to within half a percent of its all- time high yesterday based on prices, according to data starting in 1996.

U.S. Growth

Treasury yields fell earlier even as Commerce Department figures showed U.S. gross domestic product rose at a 4.2 percent annualized rate, up from an initial estimate of 4 percent and following a first-quarter contraction. Economists surveyed by Bloomberg called for a 3.9 percent gain.

“We’re starting to get a little bit of strength in the U.S. economy, but given the fact that Europe’s economy continues to weaken, that bodes well for German bunds, and U.S. Treasurys are being held up as a result of that,” ED&F Man’s di Galoma said.

Europe’s bond yields tumbled to records, and investors snapped up government securities elsewhere in search of higher interest payments. ECB President Mario Draghi said in Jackson Hole, Wyoming, last week that policy makers will use “all the available instruments needed to ensure price stability” and are “ready to adjust our policy stance further.”

BlackRock Hired

Germany’s 10-year yields touched 0.866 percent. The yield on similar-maturity French government bonds slid to as low as 1.217 percent.

The ECB has hired BlackRock Inc., the world’s biggest money manager, to advise on developing a program to buy asset-backed securities. BlackRock Solutions, a unit of the New York-based company, will provide advice on the design and implementation of a potential ABS-purchase plan, an ECB spokesman said in response to e-mailed questions. The ECB next meets on Sept. 4.

“Global yields are falling due to the ECB’s policy stance and geopolitical tension, which affects risk sentiment,” said Richard Kelly, a senior strategist at Toronto-Dominion Bank in London. “Bond purchases by the ECB are just a matter of when and not if, unless the euro region’s economy miraculously recovers. We expect the ECB to cut rates next week.”

Ukrainian President Petro Poroshenko called an emergency security meeting to defend against what he called an “invasion” by Russia after pro-Russian separatists gained ground in intensified fighting in eastern regions.

Russia has masterminded a counteroffensive by Ukrainian rebels, with more than 1,000 Russian troops operating inside Ukraine, according to NATO. France and Germany threatened Russian President Vladimir Putin with tougher sanctions.