The HitBTC cryptocurrency exchange has started to charge an additional fee for depositing bitcoins on user accounts. The reason is high commissions for transactions in the bitcoin network.

HitBTC announced that it would charge a fixed fee for all bitcoin deposits, starting from 22 December. The fee amount is 0.0003 BTC ($4.5).

"The Bitcoin network has been experiencing difficult times in the last weeks. Due to heavily increased demand, a large number of transactions passes through BTC network. It leads to a significant amount of transactions waiting in the mempool, longer processing time and unprecedented fees."

The fee will be charged even if deposits are less than the amount collected.

"If your deposit is lower or equals the fee, the whole amount will be used for the commission and will not be refunded," the exchange's statement explains.

The average commission for transactions in the bitcoin network peaked at $40 last week. Bitcoin users complain that this is higher than the average commission for a bank transfer.

HitBTC adds that "this measure is going to be introduced in order to strengthen all Bitcoin processes on HitBTC and provide stability in the functioning of the major cryptocurrency."

As of 26 December, an average transaction fee in the bitcoin network exceeds $27.