HOUSTON, March 25 (Reuters) - ExxonMobil ( XOM ) has a team in

Venezuela this week evaluating the resource in the country,

upstream head Dan Ammann said Wednesday at the CERAWeek

conference in Houston.

Ammann said there is some short-term progress that could be

made in the South American country. He said that there had been

some positive changes in terms of hydrocarbons regulation in the

country but that more would be required. Exxon - which departed

Venezuela in 2007 after its assets there were expropriated - is

also assessing the state of infrastructure in the country.

(Reporting by Sheila Dang in Houston; Editing by Nathan Crooks.)