People walks past the Supreme Court where a petition hearing to dissolve parliament by country's Prime Minister is taking place in Islamabad on Monday. AP

Pakistan's supreme court adjourned on Tuesday without ruling on the legality of political manoeuvres that led Prime Minister Imran Khan to dissolve the national assembly and call fresh elections.

The court, which will resume on Wednesday, must decide if the deputy speaker of the assembly violated the constitution by refusing to allow a no-confidence vote against Khan at the weekend.

On Tuesday the court said it wouldn't "indulge in the matter of state policy or foreign policy" in making a decision.

"Our concern is the legality of the ruling of the speaker," said Chief Justice Umar Ata Bandial.

Had the vote taken place Khan was certain to have been booted from office, but the move allowed him to get the presidency - a largely ceremonial role held by a loyalist - to dissolve parliament and order an election, which must be held within 90 days.

President Arif Alvi upped the ante Tuesday by issuing a letter to the opposition saying if they didn't nominate a candidate for interim prime minister, the process would continue without them.

Shehbaz Sharif, who would have replaced Khan had Sunday's vote taken place, said he wouldn't participate.

"The main issue is that the constitution has been abrogated," he told reporters outside the court.

"If we don't get a remedy then Pakistan will, God forbid, become a banana republic."

Khan has already nominated former chief justice Gulzar Ahmad for the role.

The opposition had expected to take power on Sunday after mustering enough support to oust him, but the deputy speaker refused to allow the vote to proceed because of alleged "foreign interference."

Khan said the opposition had gone too far by colluding with the United States for "regime change.”

The cricket star-turned-politician says Western powers want him removed because he won't stand with them against Russia and China, and the issue is sure to ignite any forthcoming election.

Agence France-Presse