Malaysian Prime Minister Najib Razak says the government will pump 20 billion ringgit ($4.6 billion) into an equity fund to support the stock market and ruled out capital controls despite the ringgit's plunge.

The Malaysian ringgit is down 26 percent from a year earlier, breaching 4 ringgit to the dollar last month, its worst level in 17 years. The stock market is down 7.5 percent in the past three months.

Najib reiterated the government has no plans to bring back capital controls. He said Monday that ValueCap, which was set up in 2012 to boost undervalued shares, will be revived with 20 billion ringgit capital.

Malaysia pegged the ringgit at 3.80 to the U.S. dollar and imposed capital curbs in September 1998 during the Asian financial crisis.