Bulent Arinc said the government could deploy "elements of the armed forces" to help quell anti-government protests in Istanbul and other cities if needed.
"Our police, our security forces are doing their jobs. If it's not enough then the gendarmes will do their jobs. If that's not enough ... we could even use elements of the Turkish Armed Forces," he said in a televised interview.
The threat came as two unions urged members to walk out and take part in a one-day nationwide strike to protest against the police crackdown on anti-government demonstrations.
The Confederation of Public Workers' Unions (KESK) and Confederation of Progressive Trade Unions (DISK) are demanding an end to the police crackdown.
However, the interior minister issued a warning to organisers of the walkout that is aimed at maintaining pressure on Prime Minister Recep Tayyip Erdogan's government.
"I am calling on public workers and labourers to not participate in unlawful demonstrations — otherwise they will bear the legal consequences," Muammer Guler said. "Our police will be on duty as usual."
A day earlier, riot police cordoned off streets, set up roadblocks and fired tear gas and water cannons to prevent anti-government protesters from converging on Istanbul's central Taksim Square, while a few miles away Erdogan addressed hundreds of thousands of government supporters.
Police maintained a lockdown on Taksim Square today, the epicenter of more than two weeks of protests, by barring vehicles. However, as the work week began, authorities re-opened a subway station at the square that had been shuttered Sunday when protesters tried to regroup.
In Ankara overnight, riot police fired tear gas and water cannons against thousands of protesters, the latest violence in a more than two-week standoff that started as an environmentalist rally but later morphed into a broader protest against Mr Erdogan's government.
Five people, including a polceman, have died and more than 5,000 have been injured, according to the Turkish Human Rights Foundation.
Riot police on Saturday emptied Istanbul's Gezi Park, next to Taksim Square, ending an 18-day sit-in by protesters against plans to redevelop the park.
Mr Erdogan, who long has been praised for shepherding Turkey to strong economic growth as many other world economies lagged, has seen his international reputation dented over his government's handling of the situation.
He has accused the protests of a plot against his government and lashed out at reports in foreign media about the situation.
Mr Erdogan is trying to reign in mass protests that have spread across Turkey – a large-scale show of anger against what many view as his government’s authoritarian policies. The protests gained momentum after police used tear gas against a peaceful sit-in in Istanbul’s Gezi Park on 31 May, objecting to the demolition of the park for a commercial development.
The protests grew into wider demonstrations against what many see as an authoritarian style of governing and Mr Erdogan's perceived attempts to impose a religious and conservative lifestyle in a country which has secular laws. Mr Erdogan, a devout Muslim, says he is committed to Turkey's secular laws and denies charges of autocracy.
The United States, which has held up Turkey in the past as an example of Muslim democracy that could benefit other countries in the Middle East, expressed concern about events in Turkey and urged dialogue between government and protesters.
"We believe that Turkey's long-term stability, security and prosperity is best guaranteed by upholding the fundamental freedoms of expression, assembly and association, and a free independent media," White House spokeswoman Caitlin Hayden said.