The parties which filed Fundamental Rights petitions included the United National Party led by sacked Wickremesinghe, the main opposition Tamil National Alliance among others.
The President removed Wickremesinghe, sacked the Cabinet and suspended Parliament last week and appointed former President Mahinda Rajapaksa as the new Prime Minister.
Wickramasinghe, who has refused to accept his dismissal, argues that he cannot legally be removed until he loses the support of parliament.
Karu Jayasuria warned on Monday that the crisis should be "settled through parliament, but if we take it out to the streets, there will be a huge bloodbath".
Guterres called on the Sri Lankan government to respect democratic values and constitutional provisions and process, uphold the rule of law and ensure the safety and security of all Sri Lankans.
