LONDON — Iraq has overtaken Iran as the second-largest OPEC oil producer for the first time since the late 1980s, a symbolic shift that signals the huge impact of Western sanctions [1] on Tehran and the steady recovery [2] of Baghdad’s energy industry.

The International Energy Agency, the Western countries’ oil watchdog, said Friday that Iraq last month produced more than 3 million barrels a day, the highest output since the U.S.-led invasion nearly a decade ago. At the same time, Iranian oil output fell below the 3 million-barrel-a-day level for the first time in more than 20 years, dropping to 2.9 million a day in July.