The Hague  - United Nations Secretary General Ban Ki-moon and Afghan President Hamid Karzai were on Monday due to arrive in the Netherlands ahead of an international conference Tuesday to discuss the future of war-torn Afghanistan.

Dutch Prime Minister Jan Peter Balkenende was due to welcome the two at a special reception in The Hague. He was also scheduled to hold talks with US Secretary of State Hillary Rodham Clinton before delivering his opening speech at the conference on Tuesday.

The conference, which was being co-hosted by the UN, Afghanistan and the Netherlands is expected to see the participation of more than 70 countries.

Dutch organizers said around 2,000 people would attend, including representatives of government and international aid organizations and hundreds of journalists.

Dutch authorities had by Monday sealed off the conference venue - the World Forum Convention Centre - and its surrounding area to traffic.

Security on the Belgium-Dutch and German-Dutch border and at Schiphol Airport was also increased, a police spokesman told reporters.

Substantial portions of the highways between Schiphol and Rotterdam Airport were also sealed to traffic to allow the international delegations to get to The Hague.

On Tuesday morning, the skies over the venue would become a no-fly zone. Around 3,000 police officers are to be deployed at the conference.

Police said five organizations, including a group representing Afghan refugees, were granted permission to hold rallies in the city centre on Tuesday.

Smaller protests would convene just outside the special security zone near the conference site. (dpa)