DUBAI: The speaker of Iran's parliament said on Sunday Tehran will never hand over images from inside of some Iranian nuclear sites to the U.N. nuclear watchdog as a monitoring agreement with the agency had expired, Iranian state media reported.

"The agreement has expired ... any of the information recorded will never be given to the International Atomic Energy Agency and the data and images will remain in the possession of Iran," said Mohammad Baqer Qalibaf.

The announcement could further complicate talks between Iran and six major powers on reviving a 2015 nuclear deal. Three years ago then U.S. President Donald Trump withdrew from the pact and reimposed crippling sanctions on Tehran; Iran reacted by violating many of the deal's restrictions on its nuclear programme.

The IAEA and Tehran struck the three-month monitoring agreement in February to cushion the blow of Iran reducing its cooperation with the agency, and it allowed monitoring of some activities that would otherwise have been axed to continue.

Under that agreement, which on May 24 was extended by a month, data continues to be collected in a black-box-type arrangement, with the IAEA only able to access it at a later date.

On Friday, the IAEA demanded an immediate reply from Iran on whether it would extend the monitoring agreement, prompting an Iranian envoy to respond that Tehran was under no obligation to provide an answer.

Iran said on Wednesday the country's Supreme National Security Council would decide whether to renew the monitoring agreement only after it expires.

U.S. Secretary of State Antony Blinken said on Friday that any failure by Tehran to extend the monitoring agreement would be a "serious concern" for broader negotiations.

Parties involved in the talks on reviving the deal, which began in April in Vienna, have said there are major issues still to be resolved before the nuclear deal can be reinstated.