(CNN) Donald Trump's Middle East peace envoy Jason Greenblatt is leaving government after two-and-a-half years spent crafting a still-unreleased Israeli-Palestinian peace plan, according to multiple administration officials.

Greenblatt, the special representative for international negotiations, is expected to leave the administration soon, likely after the Trump administration releases its proposal for resolving the Israeli-Palestinian conflict, an administration official said. Avi Berkowitz, an adviser to Jared Kushner and member of the administration's peace team, is expected to assume most of Greenblatt's duties.

Greenblatt's departure comes amid repeated delays of the release of the Trump administration's peace plan -- which was largely finalized late last year. The delays have been in large part due to an uncertain Israeli political situation. His departure, which officials attributed to family reasons, will inevitably raise fresh questions about the viability of the administration's peace efforts, since Greenblatt will not be involved in any potential direct negotiations between Israelis and Palestinians.

The Trump administration is planning to unveil its peace proposal after Israeli elections taking place in two weeks, but has not yet determined how soon after the elections to release it. Greenblatt does not yet have a firm exit date.

A former top lawyer at the Trump Organization, Greenblatt joined the administration in January 2017 with a narrow focus on the Israeli-Palestinian conflict and a plan to serve no more than two years. A senior administration official said Greenblatt was leaving -- about eight months past that marker -- to return to his wife and six children, who remained in New Jersey while Greenblatt moved to Washington to work at the White House.

Read More