Tehran: Iran’s official IRNA news agency is reporting the country’s parliament has approved an outline of a bill that allows the government to implement a historic nuclear deal reached between Iran and world powers.

The Sunday report says under the bill, the Iranian government will be authorized to withdraw from implementation of the deal if the other side fails to lift sanctions against Iran.

Final approval of the bill is expected later this week after discussion of its details.

The deal will curb Iran’s disputed nuclear programme in return for the lifting of international economic sanctions. Supreme Leader Ayatollah Ali Khamenei, who has final say on all state matters, has said it is up to legislators to approve or reject the deal. It’s not clear whether parliament will hold an up-or-down vote on the agreement, or whether a majority of lawmakers support the deal.

Larijani said Iran had expected Washington take longer to approve the deal given opposition to it in the Republican-led Congress. However, US President Barack Obama won enough Democratic support to prevent Congress from derailing the agreement or forcing him to use his veto.

A special parliamentary committee that is in charge of reviewing the deal has urged the government to stand firm in its refusal to allow inspectors to visit military sites or interview nuclear scientists.

Western nations have long suspected Iran has secretly pursued nuclear weapons alongside its civilian programme. Iran denies the allegations.