The Basel Committee on Banking Supervision's 2008 principles divide liquidity risk into funding liquidity risk and market liquidity risk. Market liquidity risk is the risk that a firm cannot easily sell or offset a position at the market price because the market lacks depth or is not working normally.
In derivatives, paying variation margin as values change and posting initial margin are cash outflows. The same principles ask banks to include in their liquidity risk analysis the possibility that counterparties demand additional collateral when the bank's own rating falls or the price of the underlying asset falls.