Pope Francis has moved to counter criticism that he is politically left-wing.

On the flight from Cuba, Pope Francis said during a half-hour press conference that his critical stance on issues such as consumerism and market economics did not mean he was a communist: "Some people might say some things sounded slightly more leftish, but that would be a mistake of interpretation." He said he was certain he had never said anything beyond what is in the social doctrine of the Church. "It is I who follows the Church. My doctrine on all this, on economic imperialism, is that of the social doctrine of the Church."

Smiling to the assembled journalists on the plane, christened "Shepherd One" for this trip, Pope Francis added: "If you want me to pray the creed, I'm willing to do it."

The Pope endeared himself to millions when on arrival at Andrews Air Force Base in Washington he opted for a tiny charcoal grey Fiat 500 instead of the traditonal limousine such as the $1 million armoured car known as "The Beast" used by President Barack Obama. During the six-day visit to the US, which straddles the three cities of Washington, New York and Philadelphia, he will use a Jeep Wrangler popemobile. Both cars are manufactured by the Italian-American company Fiat Chrysler.

Two years ago, Pope Francis told priests they should drive humble not flashy cars.

The Pope has mass popular appeal because of his ability to connect with marginalised and deprived people but conservatives in the US are already criticising him because of his views on the environment and on money, which he has said repeatedly is the "devil's dung". Catholic doctrine is traditionally to the left wing on social issues and to the right on moral issues. This can be confusing to a secular world that equates liberalism on human rights with socialist politics.

Later today, this morning in US eastern time,  Pope Francis will be the guest of honour among 15,000 people from across the political and religious spectrum invited to the White House in Washington by President Obama. There will be a papal parade in the popemobile along the Ellipse and the National Mall followed by prayers with hundreds of bishops at St Matthew's Cathedral. Tens of thousands more laity and clergy are expected at the Junipero Serra canonisation mass at the Basilica of National Shrine of the Immaculate Conception in late afternoon. Pope Francis will address Congress tomorrow before leaving for New York.