HUTCHISON Whampoa has been forced to make a clarification after the market showed uncertainty yesterday about corporate plans for a placement. At a public engagement on Thursday, Hutchison chairman Li Ka-shing was reported as saying that the company would need capital in the future and that this might lead to a placement. The stock was depressed all day yesterday, closing 40 cents down at $17.60 on a turnover of $163.52 million, the third highest of the day. Mr Li said any possible placement would occur after the expiry of the covered warrants in issue on Hutchison, due at the end of the month. In a statement issued to the stock exchange at 2.30 pm, a Hutchison representative said: ''At the request of the Stock Exchange of Hongkong, Hutchison Whampoa is making the following statement: 'With reference to recent press reports relating to the company, the company announces that it will not consider any plans for the issue or placement of shares before the end of April 1993.' '' Brokers complained that this did not clear up the uncertainty.