FINANCE Secretary Derek Mackay has said he fears the UK Government is "not too interested" in the delay to the Scottish budget.

During Topical Questions at Holyrood on Tuesday, Mackay said he has not received a response to two letters sent to the Chancellor and Shadow Chancellor of the Exchequer over uncertainty around Scotland's funding announcements.

Under the devolution settlement, a portion of Scottish funding is sent from Westminster in a block grant, which is calculated as a population share of public spending in England.

However, the snap General Election has meant the budget in Westminster has been postponed, making the amount of funding to be sent to the Scottish Parliament unclear.

Initially, Chancellor Sajid Javid announced plans for the budget to be held on November 6, with the Scottish Government prepared to announce spending proposals in early December.

The Finance Secretary said he would prefer to have a UK budget before a Scottish one, but conceded he may not have a choice.

He said: "The Scottish Government simply cannot know how much money is available to spend next year and without a new date for a UK budget, we don't know when that certainty will come.

"I've written to the Chief Secretary to the Treasury and the Chancellor and prospective Chancellor earlier this month to express concern and to stress that the UK budget should proceed as soon as possible after the General Election.

"I've not had a reply to these letters, and I therefore do not know UK ministers' comprehension of the situation, but I'm sorry to say, I fear they aren't too interested in the effect on devolution or the public services of Scotland."

Mackay said it was not just the Scottish Government who would be hit, with local authorities and public-sector bodies also left wondering.

He said: "That uncertainty continues for local government and public bodies.

"I will continue to engage with the unions, Cosla and others on the budget process but we do need the UK Government to act as quickly as they can post-election."

Mackay said he and his staff will continue to work on contingencies, so they can "productively use the time before the UK General Election to have us as well-placed as possible to respond to different scenarios".

Tory MSP Dean Lockhart pointed out that SNP MPs in Westminster voted to hold a General Election, which caused the initial delay.

Mackay replied by saying the UK Government "could have gone earlier, if they so desired".

He added: "It would appear that the Prime Minister's track record was that he couldn't get anything through Westminster, let alone a budget."