Somalia's transitional parliament has voted overwhelmingly to sack its speaker, Sharif Hassan Sheikh Adan.
Somalia's speaker wanted to have talks with the Islamists
He opposed Ethiopia's intervention and fell out with both the interim president and the prime minister.
He also called for peace talks with the Islamists who lost control of southern Somalia, including the capital, Mogadishu, last month.
Mr Aden, currently on a tour of Europe, said the Ethiopian occupation meant decisions by MPs were null and void.
The vote at the parliament in Baidoa, was carried by 183 votes to nine.
A spokesman for Mr Aden told the BBC that he did not accept the decision as not enough of the 275 members convened.
"They also voted with a show of hands, which is completely illegal," Abdirahman Ibbi told the BBC's Focus on Africa programme.
Ethiopia's Ministry of Information has denied reports that it has begun pulling its troops out of Somalia.
The government is trying to restore order in Mogadishu
It is estimated to have some 8,000 troops in the country and has said it wants them to leave as soon as possible.
Both South Africa and Tanzania have said it is too early to decide whether they will contribute troops to the proposed African peacekeeping force.
So far only Uganda has agreed to provide peacekeepers.
The South African deputy foreign minister, Aziz Pahad, said in a BBC interview that while the need was urgent, his country's armed forces were already over-stretched, with a number of peacekeeping missions in Africa.
Tanzanian President Jakaya Kikwete earlier told the BBC that any troop deployment must first be discussed with military leaders.
On Tuesday, the leaders of Ethiopia and Kenya said several African countries had offered to contribute troops to the force.
Prime Minister Ali Mohamed Ghedi named them as: Uganda; Nigeria; South Africa; Malawi and Senegal.
In a briefing to parliament, he said he expected them to be in place this month.
Over the weekend, the regional body, Igad, sent envoys to seven African countries, asking them to contribute to a proposed 8,000-strong peacekeeping force.