United Nations, July 25 - Efforts to bring stability in Nepal are suffering setbacks, Karin Landgren, the special representative of the UN secretary-general for Nepal, said here.

'The peace process has stagnated in Nepal to a certain degree,' she said at a press briefing Friday.

In the face of negative developments, the Security Council has passed a resolution that extends the stay of the peacekeeping mission in Nepal (UNMIN) for another six months to facilitate the government and other parties to work out a durable peace plan.

The key challenges that remain are drafting of a new constitution and integration of the thousands of Maoist army personnel into the main army. The government has announced the start of this rehabilitation programme.

'Critical political decisions need to be taken soon on the modalities and the number of Maoist army personnel to be integrated into the security forces,' said Landgren.

The UN representative also reported the rise of 107 armed groups in the southern region of Terai. 'On the situation in the Terai it is clear that the law and order situation is precarious,' she said.

Nepal has endured political instability since it ended nearly three centuries of monarchal rule in 2008 -- making it the world's youngest republic. In the last few months, confusion over the constitutionally mandated roles of the government and the army has impeded the reconciliation process.

In May, Pushpa Kamal Dahal Prachanda from the Unified Communist Party of Nepal-Maoist (UCPN-M), which was leading the coalition government, stepped down as prime minister following a decision by President Ram Baran Yadav of the Nepali Congress to reinstate the Chief of Army Staff whom Prachanda had fired.