US warns Iran it will step up economic pressure; two more ships attacked in Hormuz

By Jonathan Saul, Phil Stewart and Idrees Ali LONDON/PANAMA CITY, Aug 14 (Reuters) - Transit through the Strait of Hormuz appeared to grind to a near standstill on Friday after two more ships were attacked there and the United States said it could maintain a naval blockade of Iran indefinitely. A senior Iranian source said on Wednesday that there had been no progress in talks to build on a June agreement to end the war. As a ceasefire renewed then broke down, Iran has resumed attacks on ships…