(Reuters) - Nearly a third of investors in precious metals funds Central GoldTrust (>> Central GoldTrust) and Silver Bullion Trust have agreed to a bid from Canada's Sprott Asset Management (>> Sprott Inc.), a person familiar with the offer said on Tuesday.

Sprott, a Toronto-based money manager, has been trying to wrestle control of Central GoldTrust and Silver Bullion Trust from Central Fund of Canada Ltd (>> Central Fund of Canada Limited) in a rare example of a hostile bid in Canada.

The two funds are backed by physical precious metal holdings of over $750 million in gold and $44 million in silver respectively.

A source told Reuters more than 30 percent of Central GoldTrust's and Silver Bullion Trust's investors have already tendered, or committed to tender in the offer, which will expire on Sept. 18. It needs the support of two thirds of investors.

Typically, investors tender their shares or units only days ahead of the close.

Sprott has launched a tender offer where investors in Central GoldTrust can exchange their holdings for units of Sprott's Physical Gold Trust (>> Sprott Physical Gold Trust), an option that Sprott says will give an immediate boost to the value of the investments.

Sprott allows its investors to redeem their gold at net asset value, an option the Central Fund of Canada funds do not have.

Central GoldTrust trades at a 6.5 percent discount to its net asset value while Sprott's Physical Gold Trust recently traded at a 0.6 percent discount to net asset value.

If Sprott's tender for Central GoldTrust goes through, investors will receive shares in Sprott's Physical Gold Trust (>> Sprott Physical Gold Trust), which currently manages $1.8 billion in actual gold.

Julian Klymochko, a portfolio manager at Ross Smith Asset Management, a top 10 investor in both Central GoldTrust and Silver Bullion Trust, said on Tuesday he would support Sprott.

"In order for units to trade in-line with the underlying bullion, the unitholders require a physical redemption option at net asset value," Klymochko said.

The top two investors in Central GoldTrust have already said they would vote in favor of the Sprott offer.

Central GoldTrust and Silver Bullion Trust's parent, Central Fund of Canada Ltd (>> Central Fund of Canada Limited), controlled by Canada's Spicer family, has said in statements that Sprott charges higher management fees, and is not offering guaranteed premium to unit holders.

Central Fund of Canada Ltd did not respond to a request for comment.

(Reporting by Mike Stone; Editing by Carmel Crimmins and Frances Kerry)

By Mike Stone