Named range delete VBA

While trying to combine different workbooks in a folder to worksheets in a workbook. (which I have VBA code).  while running the code a message is displayed that "The name "xxxxx" already exists Click yes to use that Version of the name............" and I have to click on yes to all in all worksheets when added.

I wish to delete the named ranges in all the workbooks before combining it in one workbook. 

How could I edit the code for the same. The code using to combine the worksheet is below.

Sub Cblschcomb()
Dim fnameList, fnameCurFile As Variant
Dim countFiles, countSheets As Integer
Dim wksCurSheet As Worksheet
Dim wbkCurBook, wbkSrcBook As Workbook
Dim Sh As Worksheet
Dim Um As Range
Dim db As Range

fnameList = Application.GetOpenFilename(FileFilter:="Microsoft Excel Workbooks (*.xls;*.xlsx;*.xlsm),*.xls;*.xlsx;*.xlsm", Title:="Choose Excel files to merge", MultiSelect:=True)

If (vbBoolean <> VarType(fnameList)) Then

If (UBound(fnameList) > 0) Then
countFiles = 0
countSheets = 0

Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual

Set wbkCurBook = ActiveWorkbook

For Each fnameCurFile In fnameList
countFiles = countFiles + 1

Set wbkSrcBook = Workbooks.Open(Filename:=fnameCurFile)

For Each wksCurSheet In wbkSrcBook.Sheets
countSheets = countSheets + 1
wksCurSheet.Copy after:=wbkCurBook.Sheets(wbkCurBook.Sheets.Count)
Next

wbkSrcBook.Close SaveChanges:=False

Next

Application.ScreenUpdating = True
Application.Calculation = xlCalculationAutomatic

MsgBox "Processed " & countFiles & " files" & vbCrLf & "Merged " & countSheets & " worksheets", Title:="Merge Excel files"
End If

Else
MsgBox "No files selected", Title:="Merge Excel files"
End If

End Sub