Sri Lanka’s supreme court has suspended a presidential decree dissolving parliament and ruled that an earlier call to summon MPs is valid.

The court decided that the decree issued last Friday by President Maithripala Sirisena to dissolve the legislature will be suspended until December 7.

On October 26, Mr Sirisena abruptly ousted prime minister Ranil Wickremesinghe and replaced him with former strongman Mahinda Rajapaksa.

The supreme court complex
Sri Lankans gather outside the supreme courts complex in Colombo (AP)

A day later he suspended parliament, apparently to allow Mr Rajapaksa time to gather support among MPs.

He later ordered parliament to return on Wednesday, but then dissolved it last Friday and called for new elections in January.

Mr Wickremesinghe has refused to step down.

Opposition MP Ajith Perera said parliament will meet on Wednesday to prove that Mr Wickremesinghe has the support of a majority of his colleagues.