Liquid assets are thought of as current assets, but in practical the two terms are different. Yes, it would be wise to say that all liquid assets are part of current assets too.
Now the question arises:
What is the difference between current assets and liquid assets?
The main difference between these two arises on the basis of liquidity period. Subsequent paragraph can be refer for the same:
Current assets: These are the assets which can be converted into cash within a period of one year.
Cash, bank balance, accounts receivable, inventory, prepaid expenses etc.
Liquid assets: These assets are considered more liquid than current assets in sense that they can be converted into cash within a very short time (90 days).
Cash, bank balance, accounts receivable etc. and excludes inventory and prepaid expenses.
Liquid assets are assumed to be converted into cash at any point of time. That’s the reason why inventory (as it is difficult to convert, when needed) and prepaid expenses (cannot be converted into cash at all) are not considered as liquid assets.