The suspension of talks between Kenya's key political parties, announced on 8 April, could slow or halt progress made in returning thousands of internally displaced persons (IDPs) to their homes, humanitarian officials said.

"This [the suspension of talks] could mean that the process established to make the plans necessary for the return of IDPs could slow down or be put on hold," Jeanine Cooper, head of the UN Office for the Coordination of Humanitarian Affairs in Kenya (OCHA-Kenya), said.

"However, humanitarian agencies will continue to assist IDPs wherever they are."

The opposition Orange Democratic Movement (ODM) suspended talks with President Mwai Kibaki's Party of National Unity (PNU) on the formation of a coalition cabinet in line with an accord signed in February.

"We have resolved that negotiations ... be suspended until PNU fully recognises the 50-50 power-sharing arrangement and the principle of portfolio balance," Anyang' Nyong'o, ODM secretary-general, told a news conference in the capital Nairobi.

The ODM announcement prompted its supporters to demonstrate, lighting bonfires in the streets of a Nairobi slum.

Cooper said aid agencies had already seen the start of IDP returns and the suspension of talks could be a setback to the progress so far.

Anthony Mwangi, public relations officer of the Kenya Red Cross Society (KRCS), told IRIN the society and other aid agencies would continue helping the IDPs regardless of the outcome of the political talks.

However, he said, it was important to have a speedy resolution of the country's political issues "because this will mean speedy resettlement of the IDPs".

The European Union in a statement also expressed concern over the failure to announce a coalition cabinet on 6 April.

"The EU shares his [former UN Secretary-General Kofi Annan’s] concern and urges the parties to maintain momentum for reconciliation by forming an effective and efficient coalition government as soon as possible that reflects genuine power-sharing between Kenya's parties," the EU said on 7 April.

"This is a key milestone upon which implementation of the agreement depends."

The EU said it remained committed to support "meaningful power-sharing and to work with the new Kenyan government, once it is formed, to put Kenya back on the path to prosperity and stability".

More than 1,500 Kenyans died and an estimated 350,000 others were displaced between January and February following violence in parts of the country sparked by the disputed presidential elections held on 27 December 2007.

Since then, thousands have returned home while others have travelled to their "ancestral" homes. According to the Kenya inter-cluster team, about 202,470 IDPs remained in 235 camps as at April.

Annan brokered the coalition agreement that created a government of national unity. This accord has since been incorporated into the constitution but its implementation awaits the appointment of a cabinet.