Plaid Cymru says it will decide next week whether to attempt to lead the Welsh Assembly Government.
Future control of the Senedd in Cardiff Bay remains unclear
Leader Ieuan Wyn Jones said Plaid wanted to complete negotiations with other parties before its conclusion.
Plaid is the second biggest party in the assembly after the 3 May election, with 15 of the 60 seats.
He said Plaid was talking to Tories and Lib Dems to see if they could force Labour from office, but stressed that discussions continued with Labour.
Mr Jones set out a clear timetable for the remainder of the negotiations, saying that the shape of Wales' next assembly government needed to be clear by the end of next week.
Labour won 26 seats in the election, five short of a majority. According to the rules a new administration must be formed within 28 days of the poll to avoid a new election.
AMs may have to be recalled from their half-term break to adhere to the timetable.
After a lengthy meeting of Plaid Cymru AMs, Mr Jones told reporters that "there is no preferred option because there are no agreements".
He said: "You can only come to a preferred option when you see what the terms of any possible agreements might be.
"I have personally, and the group has collectively, declined to give a view on a preferred option because they think that that would prejudice negotiations from reaching a conclusion.
"It's only after we've concluded our discussions, when we have firm proposals to take to the group, that decisions will be made on a preferred option."
'Sustainable and stable'
On Tuesday Welsh Labour leader Rhodri Morgan said it was unlikely Labour would reach a deal to form a coalition Welsh Assembly Government.
Mr Morgan said talks would continue with the Liberal Democrats and Plaid Cymru to try to form a "sustainable and stable" minority administration.
Labour suggested that Lib Dem assembly group leader Mike German had given Mr Morgan the impression he could not deliver his party's support for a coalition.
The Lib Dems maintained that was Mr Morgan's conclusion but not theirs.
Mr German said it was "not sensible to arrive at any conclusions at this time".