The father of two young children allegedly suffocated by their mother has denied he was having an affair.

Paul Donnison received flirty text messages and emails from old school friend Alison Shimmens while trying to get back together with his former partner Fiona Donnison, the mother of his two younger children, a jury at Lewes Crown Court was told yesterday.

Mrs Donnison, 45, is accused of murdering Harry, three, and Elise, two, at her rented home in Surrey, between January 25 and January 28 last year, placing their bodies in holdalls and driving to the former family home in Sheepsetting Lane, Cross In Hand, Heathfield, with their bodies in the boot. She denies both charges.

Simon Russell Flint, defending Donnison, accused Mr Donnison of having “a little banker on the side” in case things did not work out between him and the defendant.

The court was told Mr Donnison made contact with Ms Shimmens on September 12, 2009, just 11 days after the defendant left him.

The defendant found flirty text messages on Mr Donnison’s phone from Ms Shimmens on several occasions and confronted him about them, it is alleged.

On the weekend of October 10 and 11, the defendant and Mr Donnison spent two nights in a hotel with the children.

But Mr Donnison went to stay at Ms Shimmens’ home on the evening of October 11.

When he failed to answer his phone, Donnison turned up on the doorstep and told him the reconciliation he wanted was a farce, the court was told.

Mr Donnison denied he was having an affair and said the relationship remained platonic until a weekend in January 2010.

The court was played a phone conversation between Mr Donnison and the defendant which she had recorded on September 3, 2009, two days after she had moved out of the family home.

Mr Donnison told the defendant he loved her repeatedly during the conversation and that he knew she would never stop him from seeing Harry and Elise.

He said: “You are a wonderful mother and I will never say anything less than that.

“I have seen you with Harry and Elise for the last three years, not just the way you are with them, the way you look at them, the way you treat them.

“This is why I still have g reat feelings towards you because of the way you are with my children.”

The trial continues.