The Scottish Conservative leader, who is standing to become an MSP in May, said he was “disappointed” by new Scottish Labour leader Anas Sarwar’s refusal of the offer during the Labour leadership campaign.
Mr Ross said he would happily work with any unionist party in the Scottish Parliament to boot the SNP out.
In an interview at his party’s virtual conference on Sunday with current Holyrood leader of the Scottish Tories, Ruth Davidson, Mr Ross said he would continue to put forward the suggestion of a pro-union coalition.
He said: “"I have said I would work with any party in the Scottish Parliament to get the SNP out of power.
"They have for the last 14 years failed Scotland because their No.1 priority is their party’s No.1 priority, which is to separate Scotland from the rest of the UK.
"So surely those of us who don’t believe in that, who believe in Scotland's place in the United Kingdom, can come together if we can force the SNP out.
"We know that if the SNP have a majority after the next election, the focus is not going to be on recovery, it is not going to be on rebuilding, it is going to on another referendum.
"That distracts Scottish politics and the Scottish people from the tough issues we have got to face over the next few years and that’s rebuilding the economy.
"So let’s get rid of them from government and if that means working with political parties who we will disagree with over the election campaign, but we can come together after the election to force the SNP out and get Scottish politics back concentrating on the things that matter to people, [so be it].”
He added: "I think it is sad that the Labour party seem happy to work with SNP administrations in councils across Scotland, but they’re not happy to work with other opposition parties in Holyrood to get rid of the SNP.
"I continue to make that offer. The offer is there to any party who believes in Scotland’s place in the United Kingdom, let’s work together to stop the SNP.”