Sir Mark said he and his new wife were "absolutely delighted"
Sir Mark Thatcher, the son of former Prime Minister Lady Thatcher, is reported to have remarried.
His bride was Sarah Russell, 42, the sister of Viscountess Rothermere.
Sir Mark, 54, told the Sunday Telegraph that the marriage ceremony took place in Gibraltar on 27 March, and was attended only by three friends.
Equatorial Guinea has issued an international arrest warrant over Sir Mark's alleged role in a failed coup. He denies direct involvement.
Sir Mark told the Sunday Telegraph: "Sarah and I knew from a very early stage that this was special and marriage had always seemed the inevitable outcome.
"We are both absolutely delighted that it's now official."
He was previously married for 18 years.
The couple will honeymoon in the Middle East and Indian Ocean, the newspaper reported.
On 29 March, Equatorial Guinea issued an arrest warrant for Sir Mark over his alleged role in a failed 2004 coup for which the country's attorney general said he provided money and transport.
Sir Mark was given a fine and a suspended sentence in South Africa in 2005 after pleading guilty to unknowingly helping to finance the plot.
He has always denied any direct involvement.