'necessary clarifications' is correct and usable in written English.
You could use it when trying to explain that certain topics require extra explanation or detail. For example: "Before I go any further, I think it is important to make some necessary clarifications."
"Otherwise the NPPF changes only marginally from the draft – although there have been some useful and necessary clarifications.
The IPCC 2006 Guidelines for National Greenhouse Gas Inventories [6] contain the necessary clarifications regarding Quality Control (QC) and Quality Assurance (QA) for GHG inventories.
The coordinating centre examined the translated transcripts and sought any necessary clarifications from the respective centres.
The general introduction to the questionnaire and any necessary clarifications were made electronically.
Where necessary clarifications were required, we used probes to get the innermost insights from the mothers.
I would urge the authors to make public the necessary clarifications.
Nothing and no one was harmed other than Carney's reputation; not a woman, child or – and this is an unfortunate but necessary clarification – animal.
These findings point to a further necessary clarification that greater focus on contexts in East Asians is related to attention to both objects and backgrounds, rather than a disproportionate attention towards backgrounds only.
Where necessary, clarification of data was obtained by correspondence with trial co-ordinators.
In brief, x-phi supplies the necessary clarification of conceptual content that constitutes the raw material for explication.
Further analysis on the RNA level is necessary for clarification and validation of this contention.
