The rally could not be run using studded tyres without ice as the damage to the road surface would have been too great, and it was not logistically possible to bring in a supply of gravel tyres instead.
Liepaja will now run on September 16-18 as the penultimate round of this year's ERC, while April's Canary Islands event becomes the opener.
ERC co-ordinator Jean-Baptiste Ley said: "Finding a free slot in the current calendar was not an easy exercise, as we needed to avoid any clashes with WRC events and maintain enough time for logistics between one event and the next.
"This rescheduling has allowed us to keep a perfect balance between gravel and asphalt events - which is a key asset of the ERC - and to ensure that we can run an unchanged six-round schedule in the well-known ERC Junior Championship.
"By announcing the new date as quickly as possible, we hope it will give teams and crews sufficient time to make the necessary arrangements and also allow fans to start planning for the rally weekend."
The World Rally Championship is currently facing a similar challenge going into this weekend's Rally Sweden.
The fifth Intercontinental Rally Challenge was the best yet, and it was Skoda UK driver Andreas Mikkelsen who emerged as champion from a tense five-way shootout at the season finale. Matt Beer reviews the season