Client restriction on foreign currency business was lifted immediately after China's entry into the WTO on December 11, 2001. Since then, foreign financial institutions have been permitted to provide foreign currency services to Chinese enterprises and individuals, and have been permitted to provide local currency business to all Chinese clients by the end of 2006. In 2007 five non-mainland banks were allowed to issue bank cards in China, with Bank of East Asia also allowed to issue UnionPay credit cards in the mainland (United Overseas Bank and Sumitomo Mitsui Financial Group have only issued cards in their home countries; they are not yet allowed to issue cards within the mainland). In May 2009 Woori Bank became the first Korean bank allowed to issue UnionPay debit cards (it issues UnionPay credit cards in Korea only).