Swiss banks are closing the accounts of US citizens, as the Internal Revenue Service is closing in on those who avoid paying tax. UBS and Credit Suisse have told US customers to move their money into specially created units registered in the US, or face losing their accounts. Smaller private banks, such as Mirabaud, are closing accounts altogether, Bloomberg reports. Swiss banks have to register with the Securities and Exchange Commission in order to provide services for US customers, if this is done, clients won't have the protection of Swiss banking secrecy laws. 'My bank doesn't want to do that, so we wouldn't accept an investment account for a US person,' said Pierre Mirabaud, managing partner of Mirabaud and chairman the Swiss Bankers' Association. Mirabaud has also spoken out about how nothing is easier than dodging tax in the US and UK, following the crackdown on Swiss banking secrecy by the rest of the world, saying: 'There is a feeling in the banking community, and also in the population that we are in an economic war. There is nothing easier than doing tax evasion in the US. Look at Delaware companies or trusts in the Channel Islands,' the FT reports. Swiss banks have faced mounting pressure to ease bank secrecy laws following campaigns led by the US and Germany. The situation has been further fuelled by disputes between UBS and the US, following investigations that the bank helped US taxpayers hide assets. Last week, Accountancy reported that Switzerland is making progress with the Organisation for Economic Cooperation and Development's tax standards, following an agreement to share information with the US.