Conservative lawmakers on Saturday denounced New York Mayor Edward Koch for retracting his remarks that Britain was playing a "positive role" in Northern Ireland.

"Any man who makes a strong statement and because of political pressure changes his mind is not worth the office he holds," said Terry Dicks, a Conservative member of Parliament. "He (Koch) is a weak-kneed politician who has to look over his shoulder to see where his votes lie."Koch apologized to New Yorkers of Irish descent Friday for the "unfortunate use of language" in his statement regarding the British role in Northern Ireland. He said he was wrong to suggest that the British are not an occupying army in Northern Ireland, and he urged a timetable for British withdrawal from the province.

"What I meant to convey was that there has been a modest change in the British role in Northern Ireland, a change which ought to be encouraged," the mayor said.

Koch said through a spokesman Saturday, "Having been called to task by those who are more familiar with the facts because they have a greater understanding of these 800 years of oppression, I chose to do what any honorable gentleman should do: admit my error, correct the record and say what I believe to be the truth."

His original remarks, made Wednesday after a visit to the province, were praised by British Prime Minister Margaret Thatcher.

"If more people came with an open mind and looked at what is happening . . . we would have many others making similar remarks," she told the House of Commons on Thursday.