Michael Forsyth told guests at the opening of new offices in Edinburgh for the Scottish Council of Independent Schools that details would be set out in the forthcoming White Paper on Scottish education.
Mr Forsyth used the occasion to mount a vigorous defence of diversity and choice in education, to which he said he was "passionately committed", and attacked Tony Blair, the Labour leader, for "kicking away the ladder of opportunity" by phasing out assisted places. Mr Blair attended Fettes College in Edinburgh.
Ministers clearly intend to entrench the assisted places scheme to make it as difficult as possible for a Labour government to sweep it away, which would doubly embarrass the party since that could affect its pledge to cut class sizes. The doubling of the scheme across the UK was announced by the Prime Minister in October, eventually providing 6,000 places in Scotland at a cost of Pounds 21 million.
Helen Liddell, Labour's Scottish education spokeswoman, who put a figure on the party's switch of funds into early primary for the first time at the weekend, was conscious of the limited room for manouevre Labour could face if funding for assisted places became fully committed.
"I have no intention of pursuing a vendetta against individual children, " Mrs Liddell told the Scottish Parent Teacher Council.
Mr Forsyth gave no details of his plans last week. But the independents have already suggested that the scheme could be extended to free-standing prep schools as well as those which are integral departments of secondary schools.
The Scottish Secretary brushed aside criticism that the scheme acts as a subsidy for private schools. "It is not. It is help for those whose parents would not be able to send their children to private schools. Half of those with an assisted place are from families whose income is less than Pounds 9, 000 a year.
"In Edinburgh some 1,000 youngsters benefit from an assisted place which is why I find it astonishing that people who have benefited from an independent school education in this city are prepared to kick away the ladder and deny others the opportunity which they themselves enjoyed.
"Now I just can't think who that might be a reference to."