Many Somalis were involved in a protest in Nairobi last week
Kenya has warned MPs from Somalia to stop using Nairobi as a safe haven from the chaos in their own country.
Immigration Minister Otieno Kajwang told the BBC he was on the verge of telling the MPs to register as refugees if they wanted to stay in Kenya.
The BBC's Will Ross, in Nairobi, says there are estimated to be 100 Somali MPs in Kenya at any one time.
Kenyan police arrested several Somali MPs in a round-up of people suspected of taking part in a riot last week.
Our correspondent says many Kenyans view their neighbouring country with increasing fatigue, concerned that the insecurity in Somalia could spread over their porous border.
'In their trenches'
Relations between the two countries have been strained in recent days after a demonstration in Nairobi over Kenya's detention of a controversial Muslim cleric turned violent.
Kenyan officials blamed extremists from Somalia for orchestrating the violence and arrested about 300 ethnic Somalis - charging 141 with immigration offences and releasing the rest.
Among those detained and later released were 12 Somali MPs and several government officials.
Somalia protested to Kenya over the arrests, but Mr Kajwang said his patience with the MPs was close to running out.
"The politicians causing trouble in their country and coming to hide here and reorganise how to re-launch their positions in their trenches - it is not helpful to them and not helpful to us," he said.
"We think they must take the security of their country seriously and not endlessly look for Kenya as a safe haven after destroying their own institutions."
"I think we are about to say that either you come in as refugees and you go the camps or you go back to your own country."