WASHINGTON, Aug 15 (Reuters) - US Secretary of State Antony Blinken said on Tuesday (Aug 15) he could not confirm a report that Iran slowed its pace of amassing near-weapons-grade enriched uranium but would welcome any Iranian steps to de-escalate its "growing nuclear threat".

Blinken also told reporters that Iran moving US detainees into house arrest was not related to any other aspect of U.S. policy toward Iran, which he said reflected a strategy of deterrence, pressure and diplomacy.

On Thursday, sources said Iran may free five detained US citizens as part of a deal to unfreeze US$6 billion in Iranian funds in South Korea. Iran allowed four detained US citizens to move into house arrest from prison. A fifth was already under home confinement.

The Wall Street Journal on Friday reported Iran had significantly slowed the pace at which it was accumulating near-weapons-grade enriched uranium and diluted some of its stockpile, moves that could help ease tensions with the US and revive broader talks over Iran's nuclear programme.

"Of course, we would welcome any steps that Iran takes to actually deescalate the growing nuclear threat that it has posed since the United States got out of the Iran nuclear deal," Blinken told a news conference, alluding to former US President Donald Trump's 2018 abandonment of that agreement.

Under the 2015 Joint Comprehensive Plan of Action (JCPOA) between Iran and six major powers, Iran had agreed to curb its nuclear programme to make it harder for it to obtain an atomic weapon - an ambition it denies - in return for relief from US, European Union and United Nations sanctions.

When asked if Iran's reported slowdown and the release of the detainees to house arrest was in any way linked, Blinken said they were different issues. "The agreement that we're pursuing to bring home those who are wrongfully detained in Iran is an entirely separate matter that we want to bring to a successful conclusion, and that's what I'm focused on."