US President Donald Trump met with oil executives in Washington on Friday, as he pushed for major investments in Venezuela.

But no major financial commitments were immediately forthcoming from the meeting, with the head of ExxonMobil warning the South American country was currently un-investable.

Trump has said he expects big oil companies to direct at least $100bn (£75bn) toward the country, but industry analysts have warned many companies will be reluctant to enter a situation that still carries significant risk.

Last week the US seized Venezuelan leader Nicolás Maduro, who is now being held in jail in New York.

Maduro's second-in-command, vice president Delcy Rodríguez, who is seen as more of a pragmatist, is now interim president.

Executives from the biggest US oil majors acknowledged that while Venezuela has vast proven oil reserves, they would need to see significant changes inside the country before viewing it as an attractive investment opportunity.

We have had our assets seized there twice and so you can imagine to re-enter a third time would require some pretty significant changes from what we've historically seen and what is currently the state, Exxon's chief executive Darren Woods said. Today it's un-investable.

Venezuela has a complicated relationship with international oil firms since oil was first discovered there over a century ago. Chevron is the last major American oil firm operating in the country, while companies from Spain and Italy were also present at the meeting.

Trump's discussions indicate a push to revive the nation's oil industry, proposing a deal to encourage investment but acknowledging the substantial challenge ahead.

Venezuela, sitting atop some of the world's largest oil reserves, has seen its production plummet due to disinvestment, mismanagement, and US sanctions. Current production is merely 1 million barrels per day, representing less than 1% of global supply.

Despite Trump's ambitions for $100 billion in investments, analysts indicate that political stability and security conditions must significantly improve for companies to consider committing large amounts of capital.

In summary, while Trump's call for investment in Venezuela suggests opportunity, the reality on the ground reveals a complex environment for oil companies uncertain about the risks involved.