WASHINGTON (Reuters) - U.S. President Donald Trump and Venezuela's self-proclaimed interim president Juan Guaido agreed during a Wednesday phone call to maintain regular contact amid planned protests in coming days, according to a White House spokeswoman.

Trump spoke with Guiado "to reinforce President Trump’s strong support for Venezuela's fight to regain its democracy," White House spokeswoman Sarah Sanders said in a statement. Washington has recognized Guaido, an opposition leader and head of Venezuela's national assembly, as the president of the country.

In an interview with CNN that aired on Tuesday, Guaido said he had spoken with Trump a number of times. When asked about a possible military option in Venezuela, Guaido said all options were on the table, CNN said.

Meanwhile in an interview with Moscow's RIA news agency, Venezuela's socialist leader Nicolas Maduro accused Trump of ordering his assassination while his main global backer Russia called on Wednesday for mediation in a standoff deepening geopolitical splits.

The fight to control Venezuela, which has the world's largest oil reserves, has intensified with new U.S. sanctions and legal moves that may bring Guaido's arrest.

(Reporting by Jeff Mason and Roberta Rampton; Writing by Makini Brice; Editing by Chizu Nomiyama and Jeffrey Benkoe)