Film stars are willing to act free of cost and even contribute in person towards popularising Prime Minister Narendra Modi's Swachh Bharat Mission, Union Minister for Mines, Narendra Singh Tomar said on Thursday."It is difficult for corporates to get endorsement despite paying huge sums to film actors, but today the situation is such that, even the biggest of the stars, when they get a call from the government of India for the Swachh Bharat Mission, they offer to act free of cost and are ready to contribute physically. This is a big achievement for the country," Tomar said while speaking at the 5th Indian International Metal Re-Cycling Conference which is underway in Goa."Because of Modiji's call, the issue of cleanliness has become a national issue. Today, every individual feels that they should contribute in the area of cleanliness," Tomar said.