The parents of an Israeli soldier who is being held by Hamas-allied militants received a letter from him Monday, delivered by representatives of former President Jimmy Carter.

Cpl. Gilad Schalit was abducted near the Gaza border almost two years ago. He has not been seen since, but a recording of his voice and two letters he wrote have been released.

Hamas handed over the letter as part of a promise it gave Carter during a meeting in April.

The Carter Center said the letter arrived at its Ramallah office on Sunday and was delivered to Schalit's parents, Noam and Aviva.

The center said Carter will try to arrange for a return letter to be sent from Schalit's parents to their son and continue to help mediate a deal for his release.

Israeli officials and the Carter Center would not divulge the contents of the letter. There were indications it had been written recently. Schalit's father, Noam, also confirmed receiving the letter, but refused to talk about its contents.

Egypt is mediating truce talks between Hamas, the Islamic group that rules Gaza, and Israel.

Israel has linked a truce to the cessation of arms smuggling from Egypt into Gaza and to the release of Schalit.

A top Israeli diplomatic official said the timing of the release of the letter was not accidental, coming a day before a key Israeli Cabinet meeting was set to discuss a potential military operation into Gaza. The official, who spoke on condition of anonymity because of the sensitivity of the matter, said Hamas feared an Israeli invasion and was trying to pre-empt it with the gesture.

Hamas officials in Gaza said they weren't aware of the Schalit letter.

Noam Schalit met with Prime Minister Ehud Olmert last week to get an update on talks to free his son. He has been increasingly critical of the pace of Israeli efforts on behalf of his son, who was captured in a cross-border raid in 2006 that killed two other soldiers.

Israel has reportedly agreed in principle to release 1,000 Palestinian prisoners in exchange for Schalit, but after back-and-forth talks through Egyptian intermediaries, has approved only 71 of the prisoners that Hamas wants freed, according to Carter.