Carwyn Jones faces united opposition to Labour's budget
Labour faces deadlock in the Welsh assembly over its budget after the three opposition parties lined up to oppose its proposals.
They will refuse to back the Welsh government's spending plans unless ministers make major changes.
It increases pressure on First Minister Carwyn Jones if he is to get the majority he needs to pass a budget.
His spokesman said discussions with other parties would continue.
A joint amendment from the Conservatives, Plaid Cymru and the Liberal Democrats will be discussed at a set-piece debate on the £14bn draft budget in the assembly's Senedd chamber next Tuesday. A vote on the final budget is due on December 6.
The Tories want to see increased spending on the health service, Plaid wants a boost to the enterprise budget and the Lib Dems are seeking more investment in education.
Labour has 30 of the assembly's 60 seats, making Mr Jones dependent on at least one opposition AM voting in favour or abstaining on the budget for 2012-13.
Negotiations have been underway for some weeks between the Welsh Labour leader and each of the opposition leaders to see whether common ground can be found.
Thursday's announcement of a united front from the opposition to reject his plans in their current form indicates those talks are in serious difficulty.
BBC Wales political reporter Toby Mason said it meant a serious headache for Mr Jones and Budget Minister Jane Hutt.
The opposition's amendment says the budget does not adequately address pressure on the NHS, a worsening economic crisis, the needs of disadvantaged children and financial pressure on capital projects.
The first minister on Wednesday appealed for opponents to back the budget, promising more money for skills and jobs.
But he warned there was no "magic pot" he could dip into. The budget pushed the administration's financial reserves to the limit, he said, adding that the opposition will have to explain where the axe should fall if they want to spend money elsewhere.
A Welsh government spokesman said: "We are not surprised that the other parties have various and different positions on these matters.
"We want to deliver a budget for the people of Wales and we will continue to discuss matters responsibly with the other parties."
The teaching union NUT Wales welcomed the amendment, which it said "highlights the financial pressures schools face".
NUT Wales secretary David Evans said: "We know that the per-pupil funding gap between Wales and England is currently £604 and has been widening on an alarmingly consistent basis.
"We hope that the Welsh government recognise the need to address this funding shortfall, and work to ensure that this issue is tackled as part of the budget negotiations. Failure to act now will have a significant impact on standards in future."
Welsh Lib Dem finance spokesman Peter Black said the Welsh government's plans for the economy were "lightweight".
"Labour's priorities are all out of synch with the needs of the people of Wales and this budget will do nothing for our economy, our schools and our NHS," he said.
Conservative finance spokesman Paul Davies said the amendment was tabled "in order to be constructive and in order to hold this government to account on behalf of the people of Wales".
The government's priorities were wrong, he added.
Plaid Cymru leader Ieuan Wyn Jones said: "Plaid Cymru is determined to continue to push this Labour government to take action to help our ailing economy.
"I've made it clear that we cannot support the budget in its current form, but I look forward to continued talks with the government in order to find a way forward that adequately addresses current shortcomings."