Sir Emyr Jones Parry is a former UK ambassador to the United Nations
The chair of the All Wales Convention on further assembly powers has been put forward as the UK's nomination to be EU Special Representative to Bosnia.
Sir Emyr Jones Parry is one of several candidates for the job, with EU foreign ministers hoping to agree on their nomination at a meeting on 23 February.
If successful, Sir Emyr would combine the new role with his convention work.
The convention has just begun a series of public meetings across Wales, and is scheduled to report in December.
Writing on his web blog, Plaid Cymru AM Adam Price said that if Sir Emyr was appointed it was "highly unlikely that he would be able to combine what is to all intents and purposes a full-time role with a very demanding agenda... with continuing as chair of the All Wales Convention.
"But Sir Emyr's vast diplomatic experience will stand him and the region in good stead," he added.
Liberal Democrat AM Peter Black said he doubted Sir Emyr could "run the All Wales Convention from Bosnia".
However, the Welsh Assembly Government indicated there was no question of Sir Emyr standing down from his role in Wales.
It said in a statement: "Sir Emyr Jones Parry phoned the First Minister to inform him that the government was putting his name forward, but made it clear that his nomination was conditional upon him being able to continue to fulfil his obligations in chairing the All Wales Convention, and as such would not affect his position".
The convention is a key commitment of the Labour-Plaid Cymru deal which formed a coalition assembly government after the 2007 election and is intended to prepare the ground for a referendum on full law-making powers for Cardiff Bay "at or before" the next assembly election in May 2011.
The vacancy for the position of Office of High Representative (OHR) and EU Special Representative (EUSR) in Bosnia-Herzegovina has arisen because the Slovak diplomat Miroslav Lajcak resigned the post late last month to become his country's foreign minister.
Reports coming out of the European Commission in Brussels suggest that the other candidates for the job are:
• Dimitrij Rupel - former Slovenian foreign minister
• Valentin Inszko - former Austrian ambassador to Bosnia
• Renzo Daviddi - former Chief Economist in the EU mission in Bosnia
• Michael Louis Giffoni - Italian ambassador to Kosovo
• Alexandros Mallias - Greek ambassador to the United States
Mr Rupel is currently considered the front-runner for the post.
It is hoped a consensus on the nomination can be reached by the meeting of EU foreign ministers scheduled for 23 February.
It is expected that the new EU special representative would then be inaugurated in Sarajevo between 25-26 March at the next meeting of the Peace Implementation Council - the international body overseeing Bosnia's peace implementation.
The OHR post is also expected to be closed down at that meeting.