Leaders of last week's coup in Guinea-Bissau have closed the country's air and sea borders amid rising pressure on them to give up power.

It is not yet clear if the closure announced Monday will affect a delegation from the West African regional bloc ECOWAS. The group is expected in Bissau to meet with the military chiefs who seized power Thursday, just before campaigning was to begin for a presidential run-off election.

The international community has strongly condemned the military coup and called for a return to civilian rule.

United Nations Secretary-General Ban Ki-moon said Monday that if the coup leaders go through with plans to announce a transitional government, this will only deepen the crisis in the country. He said the situation is particularly disturbing because it comes at a time when the country should be preparing for democratic elections.

A runoff election was planned at the end of this month to replace the late president, Malam Bacai Sanha, who died in January after a long illness.

ECOWAS external relations director Abdel-Fatau Musah told VOA that no one is going to allow a military to take over power in the region.

“The military there are bent on keeping that country as a failed state, for their interest and other things. And as long as that situation continues in Guinea-Bissau, the peace and security environment in the region — and indeed international security — is also endangered.”

Guinea-Bissau has endured numerous coups and coup attempts over the past 30 years and has become a transit point for international drug traffickers.

Musah said ECOWAS has budgeted $63 million for a program to reform Guinea-Bissau's defense and security sector, including restructuring and downsizing what he called the “ill-disciplined” military.

Guinea-Bissau's political parties have been in tense negotiations for several days with the coup leaders. A spokesman for the parties, Fernando Vaz, has said there will be a solution by Monday.

In the previously planned runoff election this month, former prime minister Carlos Gomes Junior, a member of the ruling party, was to face Kumba Yala, a former president who has had close ties to the military. The military junta seized Mr. Gomes and interim president Raimundo Pereira last Thursday at their homes. Their whereabouts remain unknown.

Musah said Guinea-Bissau needs a functional government without military interference to resolve all of the country's problems.