New Delhi, May 3 (PTI) : The Dirty Picture actor Vidya Balan will now feature in a "clean picture" -- ad films to propogate the government's sanitation programme.

Union Minister Jairam Ramesh, who has successfully roped in the celebrity as brand ambassador to spread awareness about the drinking water and sanitation campaign, is hopeful that her involvement will make the campaign to end open defecation a "national obsession".

"For an actor, what can be a better thing than doing a dirty picture on screen and off screen a clean picture. I think this role will work a lot because we are working on a national movement," Balan said after meeting Rural Development Minister Ramesh at his office.

"This is a clean picture (for Vidya Balan)," Ramesh quipped when reporters asked Balan if people will like her in a role to end the menace of open defecation in the country, an issue closely related to women's health and security.

"I think it is a matter great honour for me, becoming the brand ambassador of sanitation campaign. It needs to become a national obsession. I am ready to (do it) in my capacity. I am convinced," Balan, who has won the national award for her role in The Dirty Picture this year, said.

Ramesh said Balan, who will appear in ad campaigns to propagate construction and use of toilets, is actually the first brand ambassador of the Ministry.

"She (Vidya Balan) has agreed to give her time for the campaign for two years. She will be fully involved in the Nirmal Bharat Abhiyan--(the re-structured version of the Total Sanitation Campaign)," he said.

"Vidya's involvement in the campaign will help make it a national obsession," Ramesh said.

Despite being one the fastest growing emerging economies, access to adequate sanitation remains abysmally low in India compared to many other countries with similar or lower GDP.

According to UNICEF-WHO Joint Monitoring Programme Report 2010, nearly 60 per cent of India's 1.1 billion people still practice open defecation.