The main provider of Christian instruction in Victorian government schools contacted primary principals this week in an attempt to assert its right to deliver religious education.

Faced with general declining interest in special religious instruction, leading chaplaincy organisation Access Ministries sent a ''clarification'' email to all schools offering the program, while disputing its decline in popularity.

Martin Dixon. Credit:Penny Stephens

Education Department figures, based on school census data, show the number of schools taking part in religious instruction dropped by almost a third in two years - from 940 in 2011 to 666 in 2013.

Access Ministries chief executive Evonne Paddison, however, rejects the figures, saying the group taught religion in 780 of the state's schools last year.