The case was the first time a private citizen has asked the court to decide whether actions by 92-year-old Mugabe, the world's oldest leader, violated the constitution.

Mugabe, who has ruled the former British colony since independence in 1980, was last year confronted by the biggest anti-government protests in a decade. Security forces responded with teargas and water cannon.

Activist pastor Evan Mawarire, who was at the heart of those protests, was on Wednesday freed on bail by the High Court after he was arrested last week and charged with organizing demonstrations and inciting violence.

Political activist Promise Mkwananzi, whose #Tajamuka group helped organize the demonstrations, said in his application that Mugabe's response and speeches in the protests' aftermath "undermined national security and threatened citizens."

At a meeting with war veterans after one of the protests, Mugabe said his ruling ZANU-PF punished defectors during the liberation war by keeping them "underground like rats, in bunkers" - something he threatened to do to protest leaders.

Mkwananzi said Mugabe also claimed partisan control of the police and army, which is against the constitution.

But the nine-member Constitutional Court bench dismissed the case, saying Mkwananzi did not follow proper procedure in making his application. His lawyer consented to the decision.

"We are going to re-apply within 30 days in terms of the constitution, correcting those technicalities. We are not giving up," Mkwananzi told reporters after the 20-minute hearing.

Attorney General Prince Machaya, who was representing the government, made no comment to the court other than to say the case should be dismissed.

Under Zimbabwe's laws, if the top court finds that a sitting president has violated the constitution, it can order parliament to start an investigation that could lead to impeachment.

Mugabe has been endorsed as ZANU-PF's candidate for a presidential vote due in 2018 and political analysts say the ageing leader could face a divided opposition field.

Former vice president Joice Mujuru on Wednesday fired seven senior officials from her Zimbabwe People First party, dividing a movement that has struggled to gain political traction since its formation last year in March.

Mujuru said she wanted to cleanse the party because it had been infiltrated by government agents, but her decision was immediately rejected by some of the dismissed officials, who said they remained party members.