Chandy, who drove up to Raj Bhavan, handed over the resignation letter to Governor P Sathasivam.
Later talking to reporters, Chandy said the Governor had asked him to continue until alternative arrangements are put in place.
In the last five years, Chandy said he had faced lot of challenges and the Congress and the front gave him full support. He also enjoyed people's support, he said.
About media reports that he would not be taking over as opposition leader in the assembly, Chandy said he had clear views on the matter which he would convey to the party high command.
There was lot of false propaganda against the government, which the party failed to overcome, he said.
He said it was due to the people's support the United Democratic Front enjoyed, that 14 ministers and he were elected in the polls. But the media was projecting only the defeat of four ministers, he said.
"False propaganda against the government, divisive forces at work and strong undercurrents led to UDF's debacle," Chandy said. But, he said he was not blaming the people.
Besides, there was a lapse in conveying government's achievements to people, he added.
"The party and UDF faced the polls unitedly, but due to some undercurrents, leaders, including me, failed to counter it," he said, adding such a setback was completely unexpected.
He said in the last five years, UDF had set an agenda in Kerala -- development, new programmes for a section of the people which should be continued. It should be further improved and UDF will provide all support, Chandy said.
"At the earliest, let the new government come and the UDF will give all constructive help," Chandy said.
He also took a dig at the media, saying, "you should give all the support to the new government, but not the way you lent your support to me," he said, amid laughter.
On the liquor policy failing to have any impact on the electorate, he claimed the CPI-M was trying to torpedo the policy which envisages total prohibition in the next 10 years. "They have officially stated so in their advertisement."
Pointing fingers at some organisations who stood for prohibition, Chandy said, "Those who were supposed to react, failed to do so."
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