HONG KONG — China’s financial system is in the throes of a cash squeeze as the government tries to restructure the economy and punish speculators, with interbank lending rates spiking on Thursday and bank-to-bank borrowing nearly stalled.

China’s interbank and money market rates have soared over the last two weeks, and banks and other financial institutions are afraid of lending to one another. Without that lending, an economy can quickly stultify. Those in need of short-term cash, or liquidity, must pay dearly or risk default.

China’s central bank, the People’s Bank of China, has refused to provide large amounts of additional cash to the credit market. Analysts say the government is holding off for a reason: it is trying to reshape the economy while reducing its future role. The bank is not independent, unlike many other central banks, and reports to the State Council.

A huge shadow banking operation has emerged in China in recent years, with smaller banks and trust companies borrowing from bigger state-run banks and relending that money at high interest rates to private companies and property developers, a practice that fuels speculation.