Somalia’s first formal parliament in more than 20 years is to be sworn in the capital, Mogadishu, marking an end to an eight-year transitional period.Security is reported to be heavy across the city with troops and police officers patrolling the streets.After choosing a Speaker, the MPs’ main task will be to elect a new president - a vote expected within a week or two.Outgoing moderate Islamist President Sheikh Sharif Sheikh Ahmed, in power since 2009, is regarded as a favourite.Other strong candidates include Prime Minister Abdiweli Mohamed Ali and former parliamentary speaker Sharif Hassan Sheikh Aden. It is a critical moment for the country which, since the overthrow of President Siad Barre in 1991, has seen warlords, Islamist militants and its neighbours all taking a hand in its affairs.With the help of African Union peacekeepers, the interim government has been able to gain control the capital, but al-Shabab - an armed group that has joined al-Qaeda - runs many central and southern areas of the country.‘Favours and intimidation’ Members of the new parliament are to be accredited at the country’s main airport - one of the few areas of the capital considered secure. The new parliament, to be made up of a lower house with 275 members and an upper house with a maximum of 54 members, is expected to hold its first session later on Monday.So far, about 215 MPs have been chosen - enough for a quorum - by clan elders and vetted by a technical selection committee to eliminate people accused of war crimes.The MPs’ first meeting, likely to also happen at the airport for security reasons, comes on the day the mandate for Somalia’s UN-backed transitional government expires.