Mr Walls, who runs the £76m Unicorn Mastertrust, said the fund of investment trusts was now at approximately 17 per cent cash, not out of any sense of bearishness, but simply because he cannot find enough decent opportunities for investing.
He said he would invest more of this cash into his existing 54 holdings, were it not for most of these being at fair value or even looking expensive, given than some are trading a relatively high premium to the net asset value (NAV).
And as for new opportunities coming along, Mr Walls said these were just too few and far between - and while he has his eye on some investment trusts, he commented these were not looking cheap enough or at a decent enough discount to the net asset value for him to consider investing.
He said: "There's obviously lots to worry about, such as what happens with Brexit. I'm not bearish about the market and my cash holdings are not a call on the market, but I am forced to be a contrarian.
I am mindful the markets can get tough over the summer and I want to have enough liquidity to take the opportunities that might come up.Peter Walls
"People like to buy things that have gone up, which leads to discount volatility, and this forces contrarianism. I want situations that have done well but perhaps not so well recently that there is a strong valuation reason not to buy it."
Mr Walls said he has been looking at manager Neil Woodford's Patient Capital trust, as it is trading on a discount following a protracted period of underperformance, but he is not ready to commit money to it at the moment.
"I would invest more into my existing holdings, or switching into comparable investment trusts but only if there is enough of a catalyst for this", he added. "I am mindful the markets can get tough over the summer and I want to have enough liquidity to take the opportunities that might come up."
According to Mr Walls, he is more cautious about growth's ability to continue to deliver returns, especially with so much capital being committed to the Faangs and the banking sectors, so he has been adding incrementally to a more cautious, value-based positioning in the portfolio.
His comments echoed those of SDL Free Spirit fund manager Rosemary Banyard and Keith Ashworth-Lord, founder and managing director of Sanford DeLand Asset Management.
