The party members who left said they no longer wanted to be held politically responsible for the actions of their leaders, because their actions contradicted the expectations of the people and needs of the state.
According to the Baltic News Service, 658 people rallied around Nugis. The Coalition Party said the real number barely exceeds 500.
Mart Kubo, chairman of the Coalition Party, assessed Nugis's action as positive.
"We are glad we did not have to expel several hundred members ourselves," said Kubo.
Nugis' supporters, party members from regional branches of the Coalition Party, have not yet filed their applications for leaving, and neither did Nugis.
"Although Nugis declared he will leave the party on Aug. 24, nobody has seen his written request to leave," said Kubo.
Two months ago, Nugis spoke with the Estonian Democrats, a party not represented in Parliament, about organizing a new political group.
Anneli Milistver, general secretary of the Estonian Democrats, said the meeting with Nugis did not have any practical results.
"We did not receive an authorized offer from Nugis. We just hypothesized on the possibility of merging," she said.
Nugis himself declined to comment on his leaving the Coalition Party and establishing a new party.
Kubo said the Coalition Party will not suffer seriously from Nugis's actions. "We will still have about 1,000 members, and we are going to accept more this autumn," Kubo said. The Coalition Party held the majority in the former government.
As to the possible ambitions of Nugis, he will probably try to become an MP once again, according to Kubo. "But I do not generally believe in the comeback of old politicians, even if they are as famous as Nugis," he said.