In its review on the performance of the trust in the six months to June, the manager, Dunedin LLP, wrote: "The question of Scottish independence remains as uncertain as when we last reported to shareholders in March 2014. The Board continues to be concerned about the uncertainty surrounding the referendum in Scotland and will develop contingency plans as appropriate once the outcome is known in a few weeks time."
The private equity trust recorded a negative net asset total return of 1.7 per cent during the period, compared with a positive total return of 0.4 per cent for the FTSE Small Cap Index.
However, Dunedin LLP said: "The outlook for the UK market in 2014 is for a stronger second half and the manager is currently considering a number of new investment opportunities."
Dunedin said the UK economy appears to be relatively stable and the majority of its portfolio companies expect to grow earnings.
The trust made £9.8m new investments in the period, including £5.9m in EV Offshore, which makes video cameras.
It realised £2.3m by selling investments. The trust increased the valuation of its stake in Weldex, an Inverness-based crane hire firm, by £2.2m, to £8.5m.
Net assets fell to £105.4m at June 30, from £116.3m at 31 December.
The trust paid £3.6m dividends for 2013 and returned £5.2m to shareholders through a tender offer.