But India, another troop contributor, called the Council's concern misplaced.
South Africa and Australia, named as possible troop contributors, on Wednesday said they had decided not to send soldiers.
But he will act as a roving ambassador, negotiating with neighbouring countries and potential troop contributors in the next few weeks.
More than 40 countries, including both traditional troop contributors and European nations not accustomed to taking part in such missions, showed up, peacekeeping officials said.
For the major troop contributors, there are rewards - peacekeeping dividends, if you will.
Pakistani armed forces are the largest troop contributors to UN peacekeeping missions.
Washington has already lined up seven potential African troop contributors and six fellow Western donors.
Military decisions are often made in capitals of troop contributors, particularly Britain and France.
Poland, also a current troop contributor in southern Lebanon, said it would continue to take part in a new force.
For the first time France, which could emerge as a large troop contributor, laid out its vision for the force.