Acting Chechen leader Anatoly Popov says he is feeling better after an apparent weekend poisoning incident.
Popov fell ill after an official ceremony
He was flown to Moscow from Chechnya on Sunday after doctors said he had been fed an unknown toxin.
Tests are under way to determine whether it was an attempt to kill him, or just a case of food poisoning.
The incident comes a week before elections in the troubled Russian republic.
The pro-Moscow Mr Popov is not a candidate.
Doctors initially said he was in a serious condition, but he told Russian TV on Monday that he had been given the necessary treatment and was now stable.
"The situation is under control," he said, adding that he would return to Chechnya on Tuesday.
The Itar-Tass news agency cited a military source who said some bad curd cheese could have been to blame.
The Kremlin-backed candidate, Akhmad Kadyrov, is widely expected to win the presidential poll since all the other major
candidates have either been barred or have withdrawn from the race.
Until last month, Mr Kadyrov was head of the Chechen administration - he stepped down to run in the elections.
Current pro-Moscow leader Akhmad Kadyrov is the Kremlin's choice
Mr Popov, who is the republic's prime minister, took over as acting leader.
He was taken ill after attending a ceremony to open a section of a gas pipeline in the eastern district of Gudermes on Saturday.
He was later rushed to hospital in the nearby Russian base of Khankala.
Attacks by separatists on officials and commanders appointed by Moscow are common, but generally bombs and firearms are used.
In May, 53 people died when a lorry packed with explosives was crashed into a local government compound in Znamenskoye in the north of the republic.
Chechen separatist rebels have vowed to increase attacks in the run-up to the vote, which Moscow says is a crucial step towards a political settlement in the breakaway republic.
Years of armed conflict in Chechnya have left thousands of civilians and Russian soldiers dead.