In a fresh setback to the Britain’s new coalition government, former Tory Party treasurer Lord Marland stepped down as the country’s trade minister, becoming the second British minister to quit this week.

Lord Marland told British Prime Minister David Cameron he wanted to resign to resume a business career.

It comes the day after Lord Strathclyde stepped down as Leader of the House of Lords, also saying he wanted to go back to the private sector.

The first resignation was a setback for Cameron as he re-launched the Coalition with Nick Clegg at Downing Street on Monday.

Lord Marland’s decision to quit will be seen as a double blow, but the peer will stay on as the Prime Minister’s Trade Envoy to lead business delegations abroad. He will still go on planned trips to Libya, Japan and Los Angeles as part of his mission to sell Britain abroad.

A Downing Street spokesman said: “Lord Marland will be stepping down as a minister in order to focus on his role in trade promotion.”

The peer joined David Cameron’s Government as an energy minister, after a long career in the City as an entrepreneur and businessman.

He moved to the business department under Vince Cable, the Liberal Democrat Energy Secretary, in the reshuffle in September.

He was also chairman of the British Business Ambassadors by UK Trade & Investment (UKTI). During his City career, Lord Marland was a founding director of Jardine Lloyd Thomson, the insurer, and led a consortium that rescued the iconic Hunter Wellington Boots from administration in 2006.

His time as a minister has not been without controversy.

He raised eyebrows last year after joking that he was flying to Africa on an official trip to “keep the sun tan up.”

He also caused a stir by suggesting that he could add “alcohol abuse” to his official list of interests after his activities the previous evening.

His departure is likely to prompt further questions about relations within the Coalition. Lord Strathclyde stepped down on Monday saying he did not see a political career as the “cap to everything” after 25 years on the frontbench.

However, he later admitted to having had some difficulties at times with Liberal Democrat peers in the House of Lords.

According to the Telegraph, there had been reports that he told colleagues in private conversations that the Coalition had “broken down in the House of Lords“.

“I’m sure that at times over the last 18 months I may well have said that, but I think the coalition is remarkably stable,” he said on Monday night.

In a letter of to Lord Strathclyde, Cameron said he “entirely understands” the desire to pursue other interests.

He praised Lord Strathclyde as an “outstanding leader” of the Lords.