(Adds Boeing letter to Hensarling)
WASHINGTON, July 25 (Reuters) - A conservative U.S. lawmaker called on Friday for the Export-Import Bank to halt deals with Russia, but a U.S. company warned that a broader proposal to close the export credit agency would stymie a project that is helping to wean Ukraine off Russian energy.
Republican representative and Ex-Im critic Jeb Hensarling said the worsening situation in Ukraine, where government forces are fighting pro-Russian separatists, showed Russia was in direct conflict with U.S. interests and said Ex-Im should stop any financing that benefits Russian companies.
Hensarling, who chairs a House committee with jurisdiction over the lender, wants Ex-Im to close down when its charter expires at the end of September. Its prospects for survival remain uncertain as Congress approaches a summer break.
"Ex-Im's continuing - and even increasing - connections with Russian companies, many of them run by (Russian President) Vladimir Putin's cronies, has got to stop and stop immediately," he wrote in a letter to U.S. President Barack Obama.
A spokesman for Ex-Im said the bank had worked quickly to ensure it complied fully with all sanctions the United States placed on Russian individuals and companies.
In 2013, Ex-Im authorized $630 million for deals in Russia, mostly loan guarantees. Customers say they need the bank to underwrite credit that commercial lenders avoid.
New Jersey-based nuclear waste specialist Holtec International, however, said it was relying on Ex-Im to guarantee a loan for a storage facility for used nuclear fuel in Ukraine. The project would create about 200 U.S. jobs.
"Without the (Central Spent Fuel Storage Facility), Ukraine is dependent on Russia to keep its nuclear reactors running," Holtec chief nuclear officer Pierre Paul Oneid said. "We are literally at the 11th hour ... This could not have come at a worse (time)."
Big exporters such as Boeing Co have pressed House conservatives to renew the bank. In a letter to Hensarling dated Thursday that was obtained by Reuters, Boeing said "these businesses want nothing more than an opportunity to compete fairly in global markets with exporters in the 59 other countries that have similar banks."
Senator Chris Murphy, a Democrat, said legislation to extend Ex-Im bank's charter was unlikely to pass Congress next week, the last before lawmakers return to their districts for the August recess.
It is more likely to come up in September, possibly as part of a temporary move to keep funding the government.
"Short-term reauthorization is a last resort but we will not allow Ex-Im bank legislation to expire. If we have to do a short-term reauthorization, we will get that done," Murphy said on a conference call with reporters. (Reporting by Krista Hughes, additional reporting by Emily Stephenson; Editing by Dan Grebler, Nick Zieminski and Ken Wills)