From mainstream and government sources on the web, I note that a couple of new palaces are in the pipeline.
1. The new Istana Negara along Jalan Duta in KL
Artists’ impressions and other images can be found on the JKR website here.
2. Istana Kerajaan Terengganu
“Cadangan Membina Istana Kerajaan Terengganu On Lot 1796, In Mukim Cenering, District Of Kuala Terengganu, Terengganu”. Approval of the preliminary Environmental Impact Assessment (EIA) obtained in 2007 from the Department of the Environment (DoE) here. (Look under Terengganu and 2007).
A Google search also reveals an Executive Summary of the preliminary EIA on the DoE’s website here.