A controversial agreement between the Scottish Government and a Chinese firm said to be worth £10bn should be scrapped, according to Lib Dem leader Willie Rennie.

The Lib Dem leader accused Nicola Sturgeon of a "gross error of judgement" and said the agreement was "dragging Scotland's reputation through the mud".

Rennie said: "The last thing that the First Minister did before the election started was sign a £10bn deal with a business directly tied to allegations of corruption.

"The SNP have talked tough on tax avoidance and fair employment but they have rejected my calls to end government grants to companies who avoid tax or fail to pay the national living wage.

He added: "This is not simply about Nicola Sturgeon's gross error of judgement. This SNP deal is dragging Scotland's reputation through the mud. The First Minister must shred this deal."

The attack comes after allegations reported in the Herald that China Railway Group Ltd (CRG) were linked to human rights abuses in Africa.

In March 2016, China Railway No.3 Engineering Group - who are a subsidiary of CRG - signed a memorandum of understanding with the Scottish Government along with investment group Sino Fortone.

The memorandum was signed with a view to seeing up to £10bn potentially invested in Scottish infrastructure, such as housing, transport and energy.

The allegations come from a 2013 Amnesty International report, which said that a mining company controlled by CRG forcibly evicted "300 households" from their homes after being given the rights to a site in the Katanga region of the Democratic Republic of Congo in 2011.

Given only two weeks' notice, the community was taken to a new site with no housing or other facilities and "left there".

Amnesty International returned to the new site in 2012 and 2013, in both instances reporting that "their situation had not changed".

The report noted that "forced evictions are illegal under international human rights law".

Opposition party leaders in Scotland have previously expressed concerns over the agreement, due to the lack of an official publication by the Scottish Government at the time the memorandum was signed.

CRG's business history has also come under scrutiny.

In 2014, the company was blacklisted by Norway's state oil fund "due to an unacceptable risk that the company is involved in gross corruption".

In April 2016, Falkirk Council turned down a deal proposed by China Railway No.3 Engineering Group and Sino Fortone to build 1000 homes in the area, over worries that procurement laws would be breached and that local tradesmen and companies would miss out on employment.

But the SNP said no deals had yet been confirmed, and accused Rennie of "closing the door" on the possibility of billions of pounds of investment.

A party spokesperson said: "As we have made clear, the memorandum of understanding has already been published - it does not involve any agreed projects, no investment has been confirmed and no deals have been agreed.

"The SNP Government would only enter into agreements which met procurement rules and which benefited the Scottish economy.

"Any specific proposed projects would be subject to rigorous due diligence - but the stance that Willie Rennie and the Lib Dems have taken on this suggests they would close the door to potential multi-billion pound investment in Scotland."

Labour leader Kezia Dugdale said: "The more I hear about the deal the dodgier it sounds."

Dugdale added: "There's a complete lack of openness and transparency about this. We don't know what this means for Scottish jobs, for Scottish businesses and we don't know the details of some of the dark activities of the companies involved.

"I would urge the Scottish Government, as I did before, to show us the detail of this deal."

The Scottish Greens said the trade agreement raised serious ethical questions.

The party's co-convener Patrick Harvie said: "The Scottish Greens would put human rights and environmental justice at the heart of Scotland's international relationships, and the Amnesty International report on the China Railway Group leaves serious questions for the SNP about the ethics of their trade agreement.

"The Scottish Government must be absolutely water-tight when it comes to assessing potential business partners, and Green MSPs will press for early scrutiny to ensure Ministers are required to explain how closely they examined this company's environmental and human rights record before striking this deal."

The Scottish Conservatives have been approached for comment.