Yemen's president tried to defuse calls for his ouster, forcefully denying claims by opponents that he plans to install his son as his successor and raising salaries for the army.

In several days of protest, student activists and opposition groups in the Arab world's most impoverished nation — buoyed by the example of the popular revolt in Tunisia — have boldly called for the removal of U.S.-allied President Ali Abdullah Saleh.

The protests are presenting Yemen's ruler — in power for nearly 32 years — with a new and unpredictable challenge, adding to the threat from an al-Qaida offshoot aiming to topple him, a southern secessionist movement and an on-and-off armed rebellion in the north.

Seeing to quell the new outbursts of dissent, Saleh delivered a televised speech Sunday night describing talk of him aiming to bequeath power to his son as the "utmost rudeness" and insisting the rumors were untrue.

He also announced he was increasing salaries for the armed forces in a step apparently meant to ensure the army's loyalty in the face of the rising challenges.

After the Tunisian turmoil, Saleh also ordered income taxes slashed in half and instructed his government to control prices. He also deployed anti-riot police and soldiers to several key areas in the capital, Sanaa, and its surroundings to prevent riots.

Still, critics of his rule have taken to the streets in three days of protests calling for him to step down. Such calls had been a red line that few dissenters dared to cross, though Saleh has been under pressure not to extend his rule either by running again or by placing his son in power.

Saleh has long been believed to be grooming his son Ahmed, who commands the republican guard and the army's special forces, to succeed him.

"We are against succession," Saleh stressed in Sunday's speech to several hundred officers. "We are in favor of change ... and these are rude statements, they are the utmost rudeness."

He accused opposition leaders of trying to take over by rallying people to the streets "while they are hiding in the basement."

In the latest demonstrations, the main opposition groups on Monday announced a campaign to oust Saleh.

"It's about time for the political parties to lead a mass movement against the corrupt and despotic regime," Mohammed Abdul Malik, head of an alliance of opposition groups, told the rally in Sanaa.

The groups later said one of their leaders was kidnapped by people believed to be linked to the authorities.

They said Naef al-Qanis was beaten by unidentified people who later moved him to an unknown location.

Nearly half of Yemen's population lives below the poverty line of $2 a day and doesn't have access to proper sanitation. Less than a tenth of the roads are paved. Tens of thousands have been displaced from their homes by conflict, flooding the cities.

The government is riddled with corruption, has little control outside the capital, and its main source of income — oil — could run dry in a decade.

Saleh's current term in office expires in 2013 but proposed amendments to the constitution could let him remain in power for two additional terms of ten years.

Ali Seif Hassan, a Yemeni political analyst, said Saleh's speech indicates he was not likely to step down. "Saleh will run again in 2013 and will run after the next time," he said. "No Arab leader leaves power democratically to sit and write his diaries."