The main opposition leader in Togo, Gilchrist Olympio, says there is no formal deal on a unity government.
The opposition allege fraud in this, and previous, polls
Earlier, the Nigerian government had announced an agreement had been struck at talks it hosted in Abuja.
But Mr Olympio, who was barred from standing in Sunday's presidential election, told the BBC that "nothing was signed or agreed to".
Clashes between rival supporters have followed Sunday's polls - with tension high ahead of the result.
Earlier the Nigerians announced that Mr Olympio and the ruling party's presidential candidate Faure Gnassingbe had agreed a unity government, whoever won elections.
There have been violent clashes in Lome before and after the polls
But Mr Olympio told the BBC's Network Africa that he would have to consult colleagues before making any decision, but said they would not wish to be junior partners in a government after a "rigged" election.
"We are waiting for the results of last Sunday's elections and everything will depend on what the government of Togo decides to proclaim," he said.
"We think we have won and won massively despite all the restrictions and despite the massive fraud the government of Togo has carried out."
In the capital, Lome, police fired tear gas at rioting opposition supporters on Monday, who claim the election was rigged.
"If they declare Faure (Gnassingbe) the winner, this place is going to go up in flames. This is only the beginning," an opposition supporter told AP news agency.
Nigeria called the talks in a bid to calm tensions.
Togo has been ruled for the last 38 years by Gnassingbe Eyadema, who died in February.
Mr Faure, son of the late Togolese president, said: "What I want is to work with everybody in good faith and we need to go away from a bitter opposition to a healthier opposition."