Iran’s atomic energy agency said Saturday that it was deliberately violating another set of limits on its nuclear research and production that were imposed under the 2015 agreement renounced by President Trump last year.

But the details suggested that Iran was more interested in increasing pressure on European nations to find a way around American-imposed sanctions than in carrying out a full-scale effort to restore the capabilities it gave up when it struck the deal with the West.

During a news conference shown live on Iranian television, a spokesman for the agency, Behrouz Kamalvandi, confirmed that Iran had begun steps to conduct work on advanced centrifuges — the equipment that spins at supersonic speed to purify uranium, a fuel for nuclear power and nuclear weapons — in ways that are prohibited under the deal made with the Obama administration. Mr. Trump renounced the accord more than a year ago, but until four months ago Iran was continuing to comply with all of its major restrictions.

It was the third time this year that Iran had announced steps to break from those limits, saying it would no longer abide by an agreement that the United States was violating by reimposing sanctions. The accord required all signatories to lift many sanctions on Iran while it was in compliance; the European Union, Russia and China have all continued to honor the agreement, in a split from the Trump administration.