This weekend was very volatile for bitcoin. It dropped below $7,300, but on Monday its price spiked 7%, increasing up to $8,400 (see the current bitcoin price).

According to Sky News report, Twitter is updating its advertising policy in the next two weeks. Twitter is going to ban advertising of ICO, token sales and cryptocurrency wallets, as well as cryptoexchanges ads.

Remind, in January Facebook announced to block ads which promote financial products and services with "misleading or deceptive promotional activities." And last week Google reported about banning ads connected to cryptocurrency.

With this step Google and Facebook want to protect users from "online scams".

It should be noted that Twitter, in contrast to Google, has a little portion of advertising market, so its banning will not entail global consequences.

Recently, Mark Carney, the governor of the Bank of England, said: "There are a number of problems with cryptocurrencies. They are small now but they are getting bigger... There are issues for authorities who deal with money laundering, terrorist financing and price fixing. There have been a number of incidents of theft - not just big crimes but also steady thefts from people's wallets."