BEIJING, Sept 26 (Reuters) - Chinese cryptocurrency exchange Huobi Global said on Sunday it had stopped taking new mainland customers from Friday and would end contracts with mainland clients by the end of the year to comply with local regulations. China"s regulators intensified a crackdown on Friday, banning cryptocurrency transactions and mining, clarifying that overseas exchanges are barred from providing services to mainland investors via the internet. Huobi Global said in a statement it will conduct an orderly exit of its existing mainland clients on the premise that safety of their assets is guaranteed.