Rahul Gandhi gestures during an election rally. File

Gandhi was convicted last month in a case brought by a state lawmaker from the ruling Bharatiya Janata Party (BJP) after comments he made that were deemed to be insulting to Prime Minister Narendra Modi and other people surnamed Modi.

"The Surat district court has not granted a stay on Rahul Gandhi's conviction," Naishadh Desai, a local Congress leader and lawyer, told reporters outside the court room.

"We are going to challenge the decision in Gujarat High Court tomorrow. We have full faith that the judiciary will uphold justice and save democracy," he said.

While Thursday's ruling was a setback for Gandhi, his jail sentence remained suspended until he exhausts all legal challenges.

Gandhi, 52, lost his parliamentary seat in March after being convicted and sentenced to two years in jail for comments made during an election campaign rally in 2019. In India, lawmakers sentenced to jail terms of two years or more are barred from running for election.

Senior Congress leader and Supreme Court lawyer Abhishek Manu Singhvi told reporters that the party was confident that a superior court such as the high court or Supreme Court would change the ruling.

"Rahul Gandhi has not spoken anything remotely defamatory in this case, he will continue to speak for the people," he said.

During a political rally in 2019, Gandhi had referred to two fugitive businessmen, both surnamed Modi and asked: "How come all thieves have the name Modi?"

The defamation case against Gandhi was brought by Purnesh Modi, a BJP legislator in the Gujarat state assembly.

The BJP has repeatedly targeted the Gandhi family with allegations of corruption as part of its strategy to eliminate political threat from Congress, and malign the reputation of a dynasty that dominated Indian politics for decades after independence in 1947.