By Marianna Parraga

LA GUIRA, March 23 (Reuters) - Venezuela will pay Williams Cos Inc and Exterran $420 million for the 2009 nationalization of assets including a major gas injection project, the South American country's oil minister said on Friday.

"We reached an agreement of $420 million. They will drop the arbitration. They had been asking for $1.2 billion," he said.

The nationalizations in 2009 were part of a broader wave of state takeovers that targeted the assets of more than 70 smaller oilfield service companies, the majority of them Venezuelan.

During President Hugo Chavez's 13 years in power, his socialist government has put almost all the OPEC member's oil industry under state control, including multi-billion dollar projects run by U.S. majors. (Writing by Daniel Wallis; Editing by Bob Burgdorfer and David Gregorio)

Oil Minister Rafael Ramirez told reporters the deal meant the two companies would drop an arbitration case that is pending against Venezuela before a World Bank tribunal.