Paving Over a Footpath and Grass Area

Can I pave over a concrete footpath and continue paving onto the grass area to make a patio larger? Will slabs on the grass area move over time and cause cracking between them and the footpath slabs?

It is possible to pave over a concrete path by setting the slabs on a bed of mortar, but you may face a problem on the extended area due to potential sinking relative to the concrete base. The best solution is to remove the concrete path and lay a solid 15cm foundation under the area to be paved. This gives you complete control over setting the new level and is not as big of a task as it may seem.