Convicted spy Jonathan Pollard returned to prison in the U.S. on Sunday, after spending time in hospital due to his deteriorating health.

Pollard was allowed one phone call, which he used to update his wife, Esther Pollard. Esther described the telephone conversation she had with Pollard, saying “I told Jonathan that this time the president said that we are not allowed to fail.”

“Jonathan answered in a weak voice and asking me to thank the president personally, and to ask him not to stop,” she said.

Pollard’s wife said the two discussed the personal letter President Shimon Peres sent to U.S. President Barack Obama last week urging Obama to consider granting clemency to Pollard. The White House rejected Peres´ appeal, said its position hasn’t changed, and that the president has no intention to release Pollard.

“Before the conversation ended, Jonathan managed to ask whether Peres had received an answer from President Obama, and after I answered him that he had not got an answer yet, but then time was up for the conversation,” she said, adding, “I am very scared.”

Pollard, 49, was a civilian intelligence analyst for the U.S. Navy when, in the mid-1980s, he copied and gave to his Israeli handlers enough classified documents to fill a walk-in closet. He was given a life sentence.

Pollard, who was not paid when he began spying in 1984 but later began receiving several thousand dollars per month, was caught in November 1985 and arrested after unsuccessfully seeking refuge at the Israeli Embassy. He initially denied he worked for Israel, but later confessed.

His case has been a sticking point in U.S.-Israeli relations. The Israeli government, which granted Pollard citizenship, repeatedly has pressed for his release.

A 1998 U.S.-brokered peace accord between Israel and the Palestinians nearly foundered when then-prime minister Benjamin Netanyahu reportedly linked his agreement to the deal with clemency for Pollard. (© Copyright 2012 Ha´aretz 04/16/12)