Scrapping controversial tests for primary one pupils would be deeply irresponsible, Education Secretary John Swinney has said.
He accused opposition politicians, who have been calling for the standardised national assessments to be axed, of being “ill-informed” and hypocritical in much of their criticism.
The EIS teaching union also wants the tests to be scrapped after some teachers reported the assessments had left some children in tears.
The Scottish Parliament will vote on the issue on Wednesday and opposition MSPs are expected to defeat the Government, but this would not be legally binding.
Ahead of the vote, Mr Swinney issued his latest defence of the tests, urging MSPs to have a “fact-based” debate, criticising opposition claims and warning them to avoid putting party politics above children’s education.
“I am perfectly happy to have a debate on the merits of standardised assessments which is based on fact, but frankly many of the criticisms from opposition politicians have ranged from ill-informed to hypocritical,” he said.
“Some opposition politicians are now proposing to scrap P1 assessments.
“To do this would be deeply irresponsible, and parents would quite rightly never forgive any politician who puts party politics ahead of the educational interests of their children.”
Mr Swinney said all but three of Scotland’s 32 local authorities had P1 assessments prior to the national introduction, including councils run by Labour, the Lib Dems and the Conservatives.
“For those same parties to suddenly claim that there is an issue with P1 assessments when an SNP Government adopts the policy nationally reeks of political opportunism of the worst order,” he added.
“While the Scottish Government will happily listen to any constructive suggestions and continue to monitor the implementation of the policy, MSPs from all parties this week should get behind standardised assessments to ensure that teachers have access to the best possible information about the pupils they teach.”
Scottish Labour education spokesman Iain Gray said: “The facts are that the Government has tried to say that these tests are an integral part of teaching to assess strengths and weaknesses of individual pupils, and that they also provide comparative data school to school.
“They cannot do both, and the Government’s own statisticians have told them so.
“The facts are that teachers themselves have found them to be a waste of their time, and the time of their pupils.
“It is the SNP who are putting the politics of saving face above the interests of our children.”
Green education spokesman Ross Greer also accused the SNP of putting party politics ahead of education and claimed they are “ignoring” evidence on the tests.
Scottish Liberal Democrat leader Willie Rennie said Mr Swinney is “refusing to listen” after teachers, campaigners and EIS Scotland branded the tests a “waste of effort” and urged him to change course.
Liz Smith, Scottish Conservative education spokeswoman, said current evidence suggests “major issues” with the tests.