Since last month, the Eritrean government has increased pressure on the U.N. peacekeeping mission monitoring a 25-kilometer-wide buffer on the country's Ethiopian border. Eritrea first imposed restrictions on U.N. troops, then, demanded that all Western-nation peacekeepers leave by Friday.

UN peacekeepering staff get off a UN-chartered plane, at Bole International airport, in Addis Ababa

Since 2002, Eritrea has been waiting for the demarcation of a 1,000-kilometer border with Ethiopia. An independent commission drew up the new boundary as part of a complex peace accord following a two-year war that ended five years ago.

But the new border was initially rejected by Ethiopia, whose officials balked at the idea of granting Eritrea sovereignty over pieces of territory, including the flash point town of Badme. Thus, began an angry stalemate between the two nations.

Eritrea long pressured the international community to get the border demarcated, as called for in the peace deal. But last month, Asmara changed its strategy dramatically.

"Eritrea clearly is saying at this stage of the game, it is demarcate or bust," said author Michela Wrong, an expert on the Horn of Africa region. She says Asmara is pursuing a very high-risk strategy by forcing the U.N. mission from its territory and refusing to talk to Ethiopia. She says Eritrea's hardened stance has served a purpose.

"You have to hand it to the Eritrean government that they have been very successful in drawing the world's attention to what until recently has been a festering dispute that nobody had wanted to think about," she said. "Everyone in the international community has known that the issue has remained up in the air... Nobody wanted to think that thought through to its logical conclusion, which is that you have to put pressure on the party that is violating the agreement, which is Ethiopia."

Both Ethiopia and Eritrea have moved troops towards the disputed border recently. Angered by the stalemate, Eritrea has repeatedly refused to talk to top U.N. representatives and officials from Addis Ababa.

International Crisis Group Horn of Africa Project Director Matt Bryden says legally, Eritrea has every right to demand demarcation because the decision was binding and both sides agreed to abide by it. But the research analyst says there are legitimate reasons for Eritrea to start a dialogue with Addis Ababa.

"Ethiopia also wants to discuss a range of other issues, including access to the Port of Assab, ceasing support for one another's opposition and rebel groups, normalization of economic relations and so on," he explained.

Mr. Bryden says Eritrea would benefit from a longer term view, more flexibility on these issues, and says Asmara should not focus exclusively on demarcating the border.

"Eritrea rightly or wrongly perceives a number of international bodies as guarantors of the peace agreement they signed with Ethiopia - the United Nations, the African Union, European Union, United States, Algeria ... and from Eritrea's standpoint that makes them responsible for ensuring that its followed through," he continued. "And so I think that is the reason we see them putting pressure on the international community rather than Ethiopia directly."

Meanwhile, the U.N. mission is bowing to Eritrea's demands to withdraw Western peacekeepers.

Nearly 90 staff members working for the U.N. Mission in Ethiopia and Eritrea are in the process of moving from the Eritrean office to Ethiopia. The United Nations says the move is in response to Wednesday's resolution by the U.N. Security Council to pull its staff out of Eritrea temporarily, while it reviews its operations in the Horn of Africa country.

But the world body is continuing to press both sides to reach a peaceful resolution to the growing crisis.

Kofi Annan  (file photo)

"We are caught in a stalemate where Eritrea maintains implement the decision and all will be well," said U.N. Secretary-General Kofi Annan. "And Ethiopia maintains, 'Yes, we accept the decision, but we would want to discuss before we implement. And that our relationship is much more complicated than just the border ... and so we have to find a way to breaking this impasse'."

Several attempts to reach the Eritrean government for comment were unsuccessful.

So what is next for the peace process? Author Michela Wrong says it may be too late.

"I think every diplomat you talk to is very aware that these are very fragile and dangerous times... My fear is that all this effort that is being put into diplomacy between the two capitals and trying to put pressure on Ethiopia has effectively come too late," she said. "That this should have happened two or three years ago."

Nonetheless, diplomatic efforts to avert another full-scale war between Ethiopia and Eritrea are ongoing with an emergency European Union mission preparing to visit the region later this week to support the efforts of top U.N. officials.