SHANGHAI, Sept 15 (Reuters) - China's major stock indexes fell more than 2 percent in early trade on Tuesday.

China's securities regulator said late on Monday that the government's ongoing clean-up of illegal margin financing has had limited impact on the market, in a apparent move to soothe investors after major indexes fell 2 percent during the session.

The CSI300 index was down 2.4 percent to 3,201.89 points at 0130 GMT, while the Shanghai Composite Index lost 2.4 percent to 3,038.69.

China CSI300 stock index futures for September rose 0.5 percent, to 3,152.6, 49.29 points below the current value of the underlying index.

The Hang Seng index in Hong Kong was down 0.6 percent, to 21,437.11 points.

In a sign that Beijing is cranking up spending to shore up the cooling economy, fiscal expenditure jumped 25.9 percent on the year, data from the Finance Ministry showed on Tuesday.

For the first eight months, fiscal expenditure rose 14.8 percent, the data showed.

Angry Chinese authorities also have seized up to 1 trillion yuan ($157 billion) from local governments who failed to spend their budget allocations, sources told Reuters, as Beijing seeks ways to stimulate economic growth which is at its slowest for 25 years.

The huge underspend, linked to officials' reluctance to splash out on big-ticket projects while authorities crack down on corruption, supports the argument of some economists that Chinese state investment has grown too slowly this year.

August data released over the past week pointed to a further loss of economic momentum over the late summer, reinforcing expectations of further fiscal and monetary support measures.

(Editing by Kim Coghill)