No 10 has defended Boris Johnson’s decision to take a holiday in Spain this week during the energy and supply chain crisis, but struggled to explain why all MPs have been given the week off from parliament even though party conference season is over.

The prime minister is staying at a Spanish villa linked to Zac Goldsmith, the wealthy Tory peer and environment minister, who is close friends with Carrie Johnson.

No 10 refused to confirm that Goldsmith was covering the cost of the holiday in Marbella or say how the prime minister had travelled to Spain with his family.

His spokesperson insisted Johnson remained in charge with no need for Dominic Raab, the deputy prime minister, to stand in for him.

“I think everyone understands it’s right individuals are able to take a break at a suitable time,” he said, but he refused to say for how long the holiday had been in the prime minister’s diary.

The spokesperson said Johnson had taken a call from the Indian prime minister, Narendra Modi, and was being updated on the work to address supply chain problems and high energy prices.

“The prime minister continues to be in charge as is always the case,” he said. “He is in regular contact with ministers and No 10. He is also continuing to take calls, particularly in the run-up to Cop26.”

Asked about who was funding the holiday, Johnson’s spokesperson said: “Any declarations that need to be made will be made in the normal way, but I don’t have anything to add to that. I wouldn’t get into anything on location for security reasons.”

Johnson last went on holiday in August to the West Country but his break was cut short by the Taliban takeover of Afghanistan, with the prime minister returning to London after one day.

Asked about the unusual week off for MPs after the Tory party conference, a Conservative source said the three-week conference recess had been agreed by MPs before they went on their summer break.

However, there appeared to be no purpose to it because the Lib Dem and SNP conferences took place earlier in September, while the House of Commons was still sitting.

Parliament usually goes into a three-week recess for party conference season, covering the Lib Dem, Labour and Tory events. However, this year it sat during the Lib Dem conference – which was online only – and then carried on with an extra week of recess after last week’s Tory party conference.

MPs were back for three weeks after their extended summer break and they will sit for only another three weeks before another recess in November.

Earlier, Damian Hinds, the security minister, defended Johnson’s decision to go on holiday to Spain on Sky News.

“When is the right time? I think it is important that people do have an opportunity to be with their families to have some relaxing, unwinding,” he said. “But I wouldn’t want to overstate the amount of unwinding and relaxing you get to do as prime minister because, as I say, you are constantly in touch, you are constantly being briefed and you remain in charge of the government.

“What is important for the rest of us actually, for the whole country, is that the prime minister does get to have some family time, does get to have a break.”