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.

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.

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.

U.S. service company Exterran Holdings announced a $97 million non-cash charge in April 2009 relating to Venezuela's takeover of a gas injection plant controlled by U.S. firm Williams Companies and a water injection plant, which both included Exterran as a minority partner.

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.

Venezuela has about 20 cases pending against it at the World Bank's arbitration tribunal, known as the International Center for Settlement of Investment Disputes, or ICSID.

The most high profile of those were brought by Exxon Mobil and ConocoPhilips , which are seeking combined compensation of some $40 billion for takeovers in 2007.

(The story has been refiled to correct spelling of dateline to GUIRIA)

(Writing by Daniel Wallis; Editing by Bob Burgdorfer and David Gregorio)