The cash-strapped Confederation of Trade Unions is considering re-mortgaging one of its properties if it fails to obtain enough donations to cover a $1 million deficit, the organisation says. One of the two largest workers' unions in Hong Kong, the CTU may remortgage one of its offices in Nathan Road, Mongkok to settle the deficit - a result of fast expansion and reduced income. The union's permanent secretary and lawmaker Lee Cheuk-yan said operational costs had reached $9 million last year. 'Our income from organising training courses for workers has shrunk over the previous years due to a smaller market share, but our expenses have grown due to fast expansion,' he said. Mr Lee said the union would launch a voluntary donation scheme in a few months, inviting patrons to make monthly contributions of at least $50 to the group. But he expects members will give more. 'We expect 1,400 to be participating in the scheme, who will bring us an annual income of $1.2 million,' he said. Another option was to raise the membership fee, he said. A branch with fewer than 1,000 members is required only to pay $500 a year, and the contribution is capped at $3,000. The confederation may consider charging a per-head membership fee.