A coalition of landlords and letting agents has taken a step closer towards court action over the Scottish Government's rent control and eviction legislation. 

Three groups have joined together to submit a petition to the Court of Session in Edinburgh seeking a judicial review of the Cost of Living (Tenant Protection) Scotland Bill.

The emergency legislation, which was passed in October last year, banned evictions and capped rent increases at 0 per cent - effectively a freeze on increases. 

This week, ministers announced the rent cap would be extended until the end of September but would allow for one 3% increase over a 12-month period. 

READ MORE: Rent cap extended but will allow for three per cent rises from April

Tenants rights' minister Patrick Harvie said the allowance of a 3% rise, which will begin from April, recognises that "costs have been rising for landlords too".

The ban on social rent increases will be lifted from April after the Scottish Government reached an agreement with landlords – such as councils and housing associations – to keep rises below inflationary levels. 

This could see vulnerable residents in social housing face increases of up to 11%.

However, the Scottish Association of Landlords (SAL), Scottish Land and Estates (SLE) and Propertymark believe the law is "disproportionate and unfair". 

The groups argue that the law breaches the European Convention of Human Rights by discriminating against private landlords.

They say that the rent controls apply “irrespective of the financial position of both the tenant and landlord”.

It also questions the decision to remove the cap on social landlords and adds: "In the decision to remove the rent control in the social sector, the Scottish Government acknowledges the need for maintenance of these properties but has not given the same consideration to landlords in the private sector."

Chief executive of SAL John Blackwood warned that the supply of available rented properties will continue to dwindle as landlords are selling up "loss-making" properties.

READ MORE: Rental market warning as landlords sell off properties due to 'anti-landlord rhetoric'

He said: "So far, the result of the Scottish Government eviction ban and rent freeze has been just as concerning as we predicted.

"Landlords selling up loss-making property is further reducing housing supply, despite ever increasing demand.

"The result is the cost of finding a new home is actually increasing for renters.

“While the Scottish Government sees fit to raise council and housing association tenants’ rents, so social landlords can do repairs and improvements, they fail to realise that private landlords are faced with similar financial pressures.”

“The Ministerial statement in parliament last week and yesterday’s announcement make it perfectly clear the Scottish Government plans to continue with eviction ban and rent increase restrictions in the private rented sector beyond 31 March.  Landlords have had enough.”

The Scottish Government will now be asked to provide a response before the petition is considered by the Court.

However, a union representing tenants has voiced concerns over the legal challenge.

Living Rent secretary, Aditi Jehangir, said: "Landlords crying to the courts about the rent freeze despite being able to increase rents by 3% from March shows all their talk of ‘fair’ rent increases to be completely false.

"Landlords have been hiking rents to completely unaffordable levels for years. Their whingeing legal challenge reveals their anger at no longer being able to get away with it anymore."

Ms Jehangir also questioned the claim that rent increases were needed for repairs as she claimed that "over half of tenants are living in properties that have been in some state of disrepair for years". 

"Low-income tenants spend more than half of their income on rent already," she added.

"High energy and food bills and stagnant wages and now possible 3% rent increases is only adding to that perfect storm of economic misery." 

Sarah-Jane Laing, chief executive of Scottish Land & Estates, claimed the government has "has sought to unfairly penalise private landlords". 

"The decision to submit this petition is not one that has been taken lightly," she said. 

"The announcement from the Minister is too little, too late and the figure of 3% appears to be plucked from thin air.

"For too long, the Scottish Government has sought to disregard evidence provided by the sector and has been reticent in recent months to engage in any form of constructive dialogue."