Image caption The Catholic Church in the Philippines has long opposed contraception laws

A pro-contraception activist who interrupted a church service in the Philippines has been sentenced to up to 13 months in prison.

Carlos Celdran, who is also a tour guide, was demonstrating in support of new family planning laws during a mass at Manila's cathedral in 2010.

A court found Mr Celdran guilty of "offending religious beliefs" in a ruling made public on Monday.

Human Rights Watch called the verdict "a setback for free speech".

"Nobody should be jailed for voicing out an opinion or position, especially on a subject that concerns the lives of millions of Filipino women and mothers," said HRW's Asia researcher, Carlos Conde.

I am calm but I am going to fight this till the end Carlos Celdran

He called the legislation used to prosecute Mr Celdran "archaic".

Mr Celdran said he planned to appeal and remains free on bail.

"I am calm but I am going to fight this till the end," he added.

During his 2010 protest, Mr Celdran was dressed as the Filipino national hero, Jose Rizal, whose most famous book, Noli Me Tangere, features a villainous priest.

The sentencing comes fewer than two weeks after controversial new contraception laws came into effect in the Philippines.

The legislation, which require health centres to hand out free condoms and birth-control pills, and introduces sex education in schools, was approved by parliament a month ago despite fierce opposition from the Catholic Church.

More than 80% of the population in the Philippines is Catholic, and the Church is closely associated with many politicians, media commentators and businessmen.