Independent candidates are "spoilers" and they should not be encouraged, says Prime Minister Manmohan Singh. "I would like to tell the people of Mumbai that there are a lot of independent candidates in this elections. These candidates are in the fray only to dent the votes that would be received by the Congress party," he told reporters on Monday.

"They (independents) are 'spoilers'... I seek the cooperation of this vibrant city not to encourage these independent candidates because they cannot win and they are only spoilers," he said.

Maintaining that regional parties have come to stay in national politics, Singh, however, said voters should elect a "national party which has a reach all over the country, like the Congress".

"Whether regional parties are becoming stronger only time will tell, but it is a fact that regional parties have come to stay," he said. "We have to create an environment where both national and regional parties can work together.

To protect the unity and integrity of India, it is important that a national party which has a reach all over the country, like the Congress, must be encouraged," he said.