The challenger to Hugo Chávez in the Venezuelan presidential election has vowed a dramatic change in foreign policy if he is elected next Sunday, shifting his country away from China and Russia and reviewing crucial oil deals.

Henrique Capriles, who has gained ground in recent polls, said he would halt arms purchases from Russia, rethink relations with Iran and revise deals to exploit one of the world's biggest recoverable oil resources in the Orinoco belt.

In an interview during a campaign stop, Capriles said he would end the Chávez policy of promoting worldwide revolution and focus on Venezuela's needs.

"The foreign policy of this government is driven by politics – to extend a revolution worldwide. My objective with regards to foreign relations is to benefit all Venezuelans," he said.

This would mark a dramatic change. Under Chávez, Venezuela has consistently thumbed its nose at the US and moved closer to Russia, China, Nicaragua, Cuba and Iran. An example of the close friendship with Moscow came this week when Vladimir Putin presented Chávez with a Russian terrier puppy.

Capriles did not mention Russian dogs, but said Russian guns would no longer be required. "We have spent more than $14bn (£8.66bn) on arms purchases from Russia," Capriles said. "I am not going to buy more weapons. I think the policy has been mistaken."

The big question is what would happen to the oil industry in Venezuela, which vies with Saudi Arabia in claiming the biggest proven oil reserves in the world. Until now Russian and Chinese companies have struck the biggest deals for future exploitation. "We have to revise every deal. I think they are agreements that are not functioning," Capriles said.

Capriles has said he will continue to work with Beijing – because "everyone deals with China" – but he appeared ready to distance Venezuela from Iran. "How have relations with Iran and Belarus benefited Venezuela? We are interested in countries that have democracies, that respect human rights, that we have an affinity with. What affinity do we have with Iran?"

Capriles is the grandson of Jewish émigrés who escaped the Holocaust. He studied law at the Catholic University in Caracas, and says that if he wins the first thing he will do is pay homage to the Virgin Mary in El Valle on the island of Margarita.

The 40-year-old offers a sharp contrast with Chávez, who has been in power for 14 years and has had treatment for cancer throughout much of his third term.

Capriles, who spent eight months in prison after allegedly trying to break into the Cuban embassy in the days after a 2002 coup attempt against Chávez, describes himself as a political centrist "who looks to the left". Critics fear he will roll back social programmes and income redistribution initiated by Chavez.

Polls suggest the race may be tight. Some say Capriles may be leading by two points. And as the race draws to a close tensions have risen. On Saturday, two Capriles party leaders were killed by gunmen who, the opposition said, were driving a vehicle with state logos.

If the results are close many fear a period of instability. Capriles has said he will win by a wide margin and a transition will be peaceful. "I believe there will be no violence," he said. "Venezuelans have a deep democratic conviction. If the government hotheads ventured out to stir violence they would encounter the armed forces. I don't believe the armed forces respond to a political party."