RanilW is an MP, not an elected Prime Minister to challenge the President.

Maithreepala Sirisena was elected  as the President of Sri Lanka  by the people of Sri Lanka. Ranil Wickramasinghe was elected a member of Parliament from Colombo by the supporters of his political party-UNP.

The President of Sri Lanka  appointed  Ranil Wickramasinghe, who in  opinion of the President was the Member of the Parliament  who ( at that time in August,2015),  commanded the confidence of the majority in the Parliament.  It is understood that according to the Constitution  that the Prime Minister would continue to hold office as long as he Ranil Wickramasinghe is in the opinion of the President of Sri Lanka continues to command the confidence of the majority in Parliament.

In consequence the Prime Minister Ranil Wickramasinghe cannot challenge the President , if the President due to any changed  circumstances appoints another Prime Minister to replace him.

Since the 26 October,2018, the Temple Trees is occupied by the ex Prime Minister , claiming without any proof by an order issued by the Supreme to the contrary, that he is still the Prime Minister.

The Temple Trees  is a public property and the taxpayers have the right to ask why no action has been taken to evict Ranil Wickramasinghe  from the Temple Trees. 

Ranil W-MP,   may  claim in defence that he had been  removed illegally from office and that he as the former Prime Minister has the right to remain in the Temple Trees, until the New Prime Minister Mr.Mahinda Rajapakse sworn in by the President shows a majority in the Parliament.

But Ranil W- MP,  was not removed by the President, but he lost his position as Prime Minister due to some members leaving  the Cabinet.

Ranil Wickramasinghe MP, cannot claim that he is still the Prime Minister and the President swore in a new Prime Minister illegally,  as it is the right of the President of Sri Lanka Maithreepala Sirisena to take a decision when circumstances change, and it becomes necessary to appoint another Prime Minister.  It is then normal that the President would in terms of the Constitution swear in a person who in his opinion commands the confidence of a majority in the Parliament as his New Prime Minister

But if RanilW-MP, believes that he has  a majority in the Parliament, then it is for him to go to the Supreme Court and ask for an opinion about his  right to be in office and therefore to continue to reside at the Temple Trees.

The President of Sri Lanka need not  go to courts on the issue as he had been elected by the people of the country, and he has the right to act in terms of the Constitution-  acting where necessary  on legal opinion.

The Prime Minister Ranil Wickramasinge was not elected by the people, but was  only sworn in by the President as it was his opinion that at the time of swearing him in as the Prime Minister  he could command the confidence of a majority in the Parliament.

Situation has now changed and the President Maithreepala Sirisena has sworn in a new Prime Minister a member of the Parliament  who in his opinion commands the confidence of a majority in the Parliament.

It is the President’s opinion which is  necessary in terms of the Constitution and  not the necessity for  the new Prime Minister to show a majority in the parliament. The deposed Prime Minister has no right to question the new Prime Minister to show a majority in the Parliament. It is for him to show the contrary by taking a decision of the Supreme Court.

Therefore, when Ranil W –MP  lost his position of Prime Minister when the cabinet became dissolved by a number of Ministers leaving the Cabinet. Ranil W-MP has  no legal right to oppose the decision of the President of Sri Lanka.

If he  claims that he  did not loose the Office of  the Prime Minister, when a number of Cabinet Members left the Cabinet,   then he has to prove  that despite some members leaving the Cabinet he is still the Prime Minister by getting an opinion  from  the Supreme Court.

Until then he has  no right to remain in the Temple Trees. The Office of the Prime Minister Rajapakse  should serve a notice on  Ramil Wickramasinghe demanding him  to vacate the Temple Trees immediately.

If not the Government has the right to deploy the Police Force and even the Armed Forces if necessary to remove Ranil Wickramasinghe  whois illegally  occupying theTemple Trees. The Government should claim from Ranil Wickramasinghe compensation for the period he had remained in the Temple Trees.