By Paula Newton reporting from Ottawa, Canada

U.S. Defense Secretary Leon Panetta arrives in the Canadian capital Monday, where he is expected to announce new measures to support the fight against narcotics in the United States, Canada and Mexico.

He is attending a two-day meeting in Ottawa with Canadian and Mexican defense leaders."The objective is to see how we can coordinate and support on security in ways that assist the ongoing counter-narcotics strategies in our countries," said Jay Paxton, communications director for Canadian Defence Minister Peter MacKay.

The efforts will build on new strategies already in place such as Operation Martillo, a joint, interagency operation led by the Pentagon's U.S. Southern Command. It aims to team up with regional law enforcement agencies as well as other government bodies to try and hunt down drug smugglers in the waters of the Caribbean and off Central America.

The so-called war on drugs has many critics, some even within government. But U.S. government officials stress that the global nature of organized crime and the bold firepower of drug cartels means no one country or agency can go it alone.

The United Nations estimates that the drug trade in the United States, Canada and Mexico is now worth at least $147 billion a year.