The Welsh Tories say that additional budget cuts in Wales would be delayed
The Conservatives claim they will protect the Welsh budget from any further cuts in the coming financial year if they win the general election.
Welsh Conservative leader Nick Bourne made the announcement following a conversation with shadow chancellor George Osborne's office on Tuesday.
The move would postpone cuts potentially running into tens of millions of pounds until 2011-12.
But Wales' first minister said he did not believe the Tories' claims.
The news follows reports that a similar deal is being struck in Scotland between Mr Osborne and Scotland's ruling Scottish National Party (SNP).
Mr Bourne said: "I've been in touch with George's office. Wales will be treated in the same way as Scotland, which is very good news.
"I welcome it. I think people in Wales will welcome it. It's great news for Wales."
Welsh Secretary Peter Hain condemned what he called "this Tory cuts con" saying that having offered "more pain later" for Scotland they have now "added insult to injury" in Wales.
He said: "George Osborne says that Wales can have double the savage cuts in 12-months time. This plainly means it would be twice as bad for Wales in a year's time with the Tories.
"We in Wales know that this would wreck the fragile recovery and destroy jobs."
Wales' First Minister Carwyn Jones said no such offer to protect the planned Welsh budget for 2010-11 had been made to the assembly government.
He said: "We welcome any commitment that suggests we will get a protected budget. But, bluntly, I don't believe that will happen with the Conservatives and certainly no such offer has been made.
"I don't believe it would happen. I don't see how you can square on the one hand saying there will be substantial public sector cuts, as the Conservatives have said, and then say you're going to protect certain parts of the UK.
"If its been said in Scotland, it certainly hasn't been said to us in Wales."
On being told of the first minister's view Mr Bourne said: "Well, he presumably didn't know about it, did he?"
Mr Bourne said that as a planned Welsh budget had already been adopted, the decision by George Osborne's office "shows sensitivity to Wales".
If the Conservatives win May's general election, they have pledged to hold an emergency budget to speed up the task of cutting Britain's deficit during the coming financial year.
They have promised to protect health service spending, but if cuts fall in other devolved areas like transport and agriculture, then under the Barnett formula (by which Welsh spending is calculated) the assembly government's budget would also be cut.
Mr Bourne made it clear that, following the shadow chancellor's assurance to him, such Welsh cuts would be deferred until the financial year 2011-12 - not avoided altogether.
Plaid Cymru welcomed the announcement, claiming pressure they applied resulted in a Conservative "U-turn".
Plaid Cymru deputy assembly group leader Helen Mary Jones AM said: "At long last the Tories have bowed to Plaid pressure and performed this U-turn on spending cuts.
"It's a significant development that Tories have apparently conceded at last that that their cuts agenda would smash our brittle economic recovery to bits.
"But in order for people to be able to trust this commitment the Tories must be clear on exactly how they propose to make cuts to the budget of England without Wales and Scotland suffering consequential cuts."
Welsh Liberal Democrat Leader Kirsty Williams questioned how the Conservatives would make significant inroads into cutting the national debt when they'd pledged to protect spending on health, international development, Scotland and Wales in turn.
"One has to wonder how their plans add up," she said.
Shadow chancellor George Osborne told BBC Scotland's 'The Politics Show' he would allow Scottish ministers to spread the pain of any additional cuts to their 2010-11 budget over two years.
Mr Osborne said: "Because the budget has passed through the Scottish Parliament for 2010-11, we will respect that."