"The government's words have not been matched by action for this drive. It should try to more meaningfully contribute in terms of resources, material and direction to the Swachh Bharat Abhiyan," the former Union minister said.
The publicity being done for the mission is "terrific", Tharoor said, but a more concerted endeavour is required to achieve its objectives, he added.
Recalling work done on the cleanliness front by him in Kerala, Tharoor, Lok Sabha MP from Thiruvananthapuram, said that while the streets and localities are cleaned of garbage, it must also be ensured that the waste thus collected finally ends up at a treatment plant.
Reiterating that more funds are needed to be allocated for the mission, he claimed that the government's publicity budget for the Swachh Bharat Abhiyan was larger than that for meeting its sanitation goals.
Launching his ambitious drive to ensure a comprehensive clean-up of urban India, Modi had last year nominated nine eminent personalities, among whom were the likes of cricket legend Sachin Tedulkar, industrialist Anil Ambani and actor Salman Khan, to spread the message of the Swachh Bharat Abhiyan.
Tharoor too was named in the list of nominees and had said that he was "honoured" to accept the Prime Minister's invitation, something that had seen the Congress leader come in for criticism within party circles.