Jeremy Corbyn has said Labour may have to go into next year's Holyrood elections without having a clear position on Trident.
The Labour leader, who is visiting Scotland, said he hoped the position would have been resolved by then.
But he told BBC Scotland that he could give no guarantee.
Mr Corbyn is opposed to nuclear weapons but his party is presently committed to renewing the Trident system, which is based on the Clyde.
He said on Wednesday that he would not fire Britain's nuclear weapons if he were prime minister, with his comments being criticised by some senior Labour colleagues.
His visit to Scotland came four months after Labour lost 40 of its 41 Scottish MPs to the SNP in the general election.
Former Scottish Labour leader Johann Lamont resigned in December of last year, saying the Scottish party was being treated as a "branch office".
Left-winger Mr Corbyn, who won the leadership of his party last month, said his priority was winning back votes in Scotland and insisted he would not interfere in the "operation" of Scottish Labour.
Speaking to journalists outside the Scottish Parliament on Thursday, he said: "We're doing great, party membership is going up after my first conference as leader and things are going really well."
The Holyrood election takes place in May of next year when Scottish Labour, now led by Kezia Dugdale, will be defending 38 seats.
Speaking ahead of the visit, Mr Corbyn said: "Under my leadership there will be no question about who is in charge of the Scottish Labour Party.
"Kezia Dugdale is leader of our party in Scotland and I will be working alongside her to win back support for Labour."
He added: "Kez has said that she wants to make absolutely clear what the Labour Party stands for and who we stand with. That is also my mission across the UK.
"Too many people have told me that they think the Labour Party lost its way. We need to win back their trust by showing them exactly what difference a Labour government would make to their lives.
"The stakes are high for Scotland. People can't afford a Tory government whose policies are making people work harder for less or an SNP government that is intent on having the arguments of the past rather than looking to the future."
He visited the Scottish Parliament to meet MSPs before also meeting trade unionists and party activists.
The SNP had earlier challenged Mr Corbyn to use his visit to end what it termed "the chaos and confusion" over Labour's policy on replacing the Trident nuclear weapons system.
SNP deputy leader Stewart Hosie said: "Labour's position on Trident has become utterly indefensible.
"After days of chaos and infighting, Jeremy Corbyn must use his trip to Scotland to make clear whether he is leading Labour - or whether Labour is leading him.
"Jeremy Corbyn needs to be straight with the people of Scotland - will Labour oppose Trident nuclear weapons on our shores, or simply allow the Tories to go ahead with this outdated and unwanted project."