British Prime Minister David Cameron arrives at the European Council headquarters ahead of the European Union (EU) summit in Brussels, Belgium, October 23, 2014. (Xinhua/Gong Bing)

President of European Council Herman Van Rompuy arrives at the European Council headquarters ahead of the European Union (EU) summit in Brussels, Belgium, October 23, 2014. (Xinhua/Gong Bing)

European Council President Herman Van Rompuy (C) holds his grand children to attend familyphotos with EU leaders during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) holds his grand children to attend familyphotos with EU leaders during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) holds his grand children to attend familyphotos with EU leaders during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)  European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) presents his grand children to Italian Prime Minister Matteo Renzi (L) and outgoing European Commission President Jose Manuel Barroso prior to familyphoto session during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

Grandchildren of European Council President Herman Van Rompuy attend a familyphoto session during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children as they prepare to pose for familyphotos with EU leaders during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) presents his grand children to Italian Prime Minister Matteo Renzi when they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children and EU leaders as they prepare to pose for familyphotos during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

Outgoing European Commission President Jose Manuel Barroso (L), President-elect of the European Commission Jean-Claude Juncker (R) and German Federal Chancellor Angela Merkel (back) attend familyphoto session during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

Outgoing European Commission President Jose Manuel Barroso (L) chats with President-elect of the European Commission Jean-Claude Juncker (R) as German Federal Chancellor Angela Merkel (back) stands behind during familyphoto session at the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

European Council President Herman Van Rompuy (C) is accompanied by his grand children as they prepare to pose for familyphotos with EU leaders during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)

German Federal Chancellor Angela Merkel (R) talks with Luxembourg Prime Minister Xavier Bettel at familyphoto session during the EU Summit at the EU Council headquaters in Brussels, Belgium, Oct.23, 2014. (Xinhua/Ye Pingfan)