Monique Wong, senior portfolio manager at Coutts, told the Today programme she expects June's government borrowing figures, which will be announced this morning, to stand at between £3bn and £4bn.
The number shows how much government spending exceeds tax receipts.
"The labour market data is healthy, the unemployment rate is at a multi-decade low, wages are rising faster than inflation so the tax take will continue to be in good shape," said Ms Wong.
"In terms of the spending, we saw an increase in departmental spending around the end March Brexit date so a good guess would be that that was to do with contingency planning."
"So my guess is for the June number is that will ease."