Negotiations over Iran’s nuclear program appeared headed for double overtime on Wednesday, beset by competing claims after diplomats abandoned a March 31 deadline for the outline of a deal and agreed to press on.

German Foreign Minister Frank-Walter Steinmeier said negotiators were still facing a “tough struggle,” indicating the talks were not likely to end anytime soon. And other officials indicated the efforts, already extended into Wednesday, probably would drag into Thursday.

Iran and six powers have been locked in haggling over what an initial understanding should look like for nearly a week, reflecting the significant gaps facing them.

Steinmeier said he hoped that when the talks end “we won’t just be reporting about closing gaps” but also will be providing details of agreement on important points. His comment reflected unhappiness with Iran’s insistence that the Lausanne talks should end only with a vague statement of principles.