The release of imprisoned pastor Saeed Abedini was not secured as part of the nuclear deal agreed between Iran and six major world powers including the US, his wife has confirmed.

Naghmeh Abedini, who has campaigned relentlessly for her husband's release since his arrest in 2012, has issued a statement urging the Obama Administration to reconsider.

"I plead with Congress to ensure that my husband, an American citizen, is not left behind," she said.

"With the announcement of a deal and yet silence as to the fate of Saeed and the other Americans held hostage in Iran, their fate lies now in the hands of Congress. I plead with each member of Congress to review the deal with our family at the forefront of their thoughts.

"Congress holds the key to bringing my husband home, to returning the father to my children. My children have desperately missed the loving embrace of their father for the last three years of their lives. They have grown up almost half of their lives without their father. Please help us ensure the remainder of their childhood includes both a mother and a father."

The American Centre for Law and Justice (ACLJ), which is supporting Naghmeh in her campaign, branded the nuclear deal "unconscionable" because of its failure to secure Saeed's release.

"It is unconscionable that the Obama Administration would sign a deal with Iran without securing the freedom of Pastor Saeed who has been imprisoned for nearly three years simply because of his Christian faith," a statement from the ACLJ's chief counsel Jay Sekulow said.

"President Obama told the Abedini family face-to-face that he considered the release of Pastor Saeed a 'top priority.' How could that be a "top priority" when a deal is reached and Pastor Saeed is left behind? What happened today makes a bad deal even worse. We will now focus our attention on convincing Congress to reject this deal."

Sekulow was referring to a private meeting that Naghmeh secured with Obama in January. She told Christian Today that though the president did assure her that Saeed's release was a priority, every time she went to say something about her husband, she felt God leading her to use the time to minister to Obama instead.

"It was encouraging for President Obama to meet with me, not just for me but for millions of Christians who've been watching the situation and praying," she explained.

"I knew he was avoiding the meeting so as not to upset the Iranian government, and so to have met with me – I see God's hand in it. [But] I felt the Lord telling me this meeting is more for President Obama.

"He [Obama] was surprised that I spent the time sharing God, and telling him that we as Christians pray for him and love him," she added. "I was able to share God's love with him, and it was a good time for making a personal connection."

In an update on her Facebook page today, Naghmeh wrote: "Many of you have asked if Saeed was part of the nuclear deal that was reached with Iran a few hours ago. I am sorry to say that Saeed was NOT part of the deal and that State Department has NOT provided any assurance of Saeed's release.

"The Lord has been preparing me for this. Our hope is in the Lord. We had all prayed that God would deliver Saeed and that He would get all of the Glory and this is exactly what is happening.

"Thank you for your continued prayers. Our family needs it and appreciates it."

She ended with a verse from Psalm 121:

"I will lift up my eyes to the hills —

From whence comes my help?

My help comes from the Lord,

Who made heaven and earth."

Saeed is currently serving an eight year prison sentence in Iran for "threatening the security of the state". He began developing home church communities for Christian converts, who are forbidden from gathering in Iran's public churches, more than a decade ago. He was first arrested in 2009, but was later released after pledging to stop formally organising house churches in the Musilm-led country.

He was arrested for a second time upon returning to Iran in 2012 to help build a state-run, secular orphanage and was held without charges until January 2013, when he received his eight-year sentence.