The state of emergency in the popular Indian Ocean tourist destination is to last 30 days, the ministry said, citing a national security threat.
The government of the Maldives, an archipelago of coral islands off the southern tip of India, has been in turmoil in recent weeks.
In late October, state-run TV reported that Vice President Ahmed Adeeb had been arrested and charged with treason in connection with an alleged assassination attempt on President Abdulla Yameen. Adeeb has denied the charges
The incident in question was a blast aboard a speedboat carrying Yameen and his entourage
on September 28. The president emerged unscathed from the explosion, but his wife and two others were wounded.
On Monday, security forces defused an explosive device -- a stick of dynamite attached to a remote detonator -- that had been planted in a vehicle parked near Yameen's official residence in Male, the capital, the Ministry of Foreign Affairs said
Imprisonment of ex-President criticized
This is the latest round of the political unrest that has been buffeting the Maldives for years. The turbulence hasn't so far stopped affluent tourists, lured by the country's white sandy beaches, from visiting.
In 2012, former President Mohamed Nasheed, the country's first democratically elected leader, was ousted amid opposition protests. He says he was forced out in a coup orchestrated by former ruler Maumoon Abdul Gayoom.
A court sentenced Nasheed to 13 years in prison on terrorism charges in March. The U.N. Special Rapporteur on the independence of judges and lawyers, Gabriela Knaul, said the proceedings against the former President lacked "respect for the most basic principles of fair trial and due process."
Nasheed's party expressed concern
over the declaration of the state of emergency just two days before it planned to hold a large protest, calling it "a desperate attempt, by a President who is losing his grip, to cling onto power."
"Yameen has jailed or threatened every opposition leader, placed criminal charges against 1,700 opposition activists, and is now turning on his own by jailing the vice president," said Hamid Abdul Ghafoor, a spokesman for the Maldivian Democratic Party.
Concerns over tourism industry
The office of Adeeb, the jailed vice president, called the state of emergency "a fundamental attack on the freedoms and rights enjoyed by our citizens provided by our Constitution"
and said it could hurt the economy by prompting other governments to issue travel warnings.
The country's Tourism Ministry said after the declaration of the state of emergency that "all tourism-related businesses will be operating as usual and the situation in the Maldives remain(s) stable."
The British government issued updated advice
for travelers to the Maldives on Wednesday, telling them to "take extra care and follow local advice."